The free agent season that begins every year on July 1 can be a high-risk, high-reward situation. For some teams, it marks the date when they acquired the final few key pieces that guided them to Stanley Cup contention; for others, it's the day they locked themselves into a long-term cap prison of their own making.
Hockey analytics can help provide an interesting perspective on which players might be value-priced additions, and which signings may ultimately prove regrettable. By incorporating age, past results, projected cap hit and a player's usage into a statistical model, we have built an All-Value Team and an All-Risk Team composed of the players most likely to find themselves in one category or the other.
Click here for a peak at the methodology used in coming up with the predicted contract and expected value for each player. Let's start off with the All-Value Team:
All-Value Team
Antoine Roussel, LW
Predicted contract: Four years, $2.5 million per year
Expected value: minus-1.1 goals (over four years)
Age: 28
With only five goals in 73 games last season, having never scored 30 points in a season, and a projected impact of minus-1.1 goals over the next four seasons, it may appear that we accidentally started with an entry from the wrong team. However, Roussel's shot-based metrics warrant special attention.
During the past two seasons combined, the Stars have bested their opponents 1,571-1,364 in 5-on-5 shot attempts when Roussel has been on the ice, which is a 53.5 percent ratio. That's up 2.1 percent from when he's not on the ice, 51.4 percent. Those results are especially remarkable when you consider that he had the disadvantage of starting 518 shifts in the defensive zone, and 384 in the offensive zone -- a 42.6 percent rate that was the third-lowest zone start percentage among the team's forwards who played a minimum of 40 games.
Visually, Roussel's usage and shot-based metrics can be viewed on the following player usage chart of the most prominent UFA forwards. As always, zone start percentage is on horizontal axis, quality of competition is on the vertical, and the colors denote the team's shot-based metrics with the given player on the ice -- blue is good, red is bad. Roussel is the lone blue circle on the left, defensive side of the chart, making him ideal for any team's third line.
Matt Stajan, C
Predicted contract: One year, $1 million
Expected value: plus-4.1 goals
Age: 34
Clearly, Stajan is not an offensive threat. Over the past seven seasons, only nine forwards have scored fewer than his 143 points in more than his 455 games. And, at age 34, he's unlikely to improve. However, Stajan isn't valuable for his scoring, but for his ability to shut down all opposing on-ice activity while the top six is catching its breath.
How effective has Stajan been in this role? As modest as his own scoring has been, Calgary has actually outscored their opponents during that time span when he has been on the ice. Last season, opponents scored just 15 goals in 68 games while Stajan was on the ice at even strength, the fewest of anyone who played at least 60 games. During the past four seasons, the Flames allowed just 93 goals in 288 games with Stajan on the ice at even strength.
Yes, Stajan has carried an excessive cap hit between $3.125M and $3.5M since 2010-11, but that is expected to be sharply reduced this summer. If so, he could be the right fit on virtually any team's fourth line.
Jannik Hansen, RW
Predicted contract: One year, $800,000
Expected value: plus-4.1 goals
Age: 32
Consistently a healthy scratch in the regular season and throughout the playoffs, Hansen didn't have much of a chance to showcase his talent with San Jose last season. Even when he was used, it was for an average of 12:02 minutes per game on the depth line.
Given that usage, it's easy to forget that Hansen is only two seasons removed from scoring 22 goals on Vancouver's top line in 2015-16, and finishing second on the team to Daniel Sedin with 36 even-strength points.
Bound to be a tremendous bargain, Hansen still has the potential to be a fast, two-way winger who can mix it up in the corner, backfill the penalty kill, and provide a little additional scoring from the bottom six.
Michal Kempny, D
Predicted contract: Two years, $1.25 million per year
Expected value: plus-9.4 goals (over two years)
Age: 27
By reaching the Stanley Cup Final as an expansion team, the Vegas Golden Knights demonstrated that teams can be successful with a blue line composed of those who were previously in secondary roles. Unless that was a fluke, it should generate interest in the league's best third-pairing defensemen, including someone who was on the winning side of that series, Kempny. When Kempny was given an opportunity to partner with John Carlson, he proved up to the task.
But it wasn't all Carlson; Kempny's shot-based metrics help him stand out as one of the best depth defensemen. In 103 career games, Chicago and Washington have outshot their opponents 1,581-1,368 with Kempny on the ice at 5-on-5. That works out to a Corsi for percentage of 53.6 when he's on the ice, compared to 50 percent when he's not.
If teams do not believe that Kempny is truly ready for a top-four opportunity, then the alternative is to invest three times as much per season in a mediocre second-pair option, and over an even longer term, as we saw with recent free agents like Karl Alzner, Trevor Daley, Dan Girardi, Erik Gudbranson, Dmitry Kulikov, Kris Russell, Justin Schultz, Brendan Smith and Michael Stone. Compared to those options, extending an opportunity to someone like Kempny is well worth the risk.
Thomas Hickey, D
Predicted contract: Two years, $2.7 million per year
Expected value: plus-1.6 goals (over two years)
Age: 29
Based on the following player usage chart of free-agent defensemen, Hickey may be a cost-effective way for a team to complete their top four. He's the nice blue circle right on the horizon and on the left, defensive side of the chart right next to Alexei Emelin and Jack Johnson. Not only did Emelin and Johnson command far greater cap hits of $4.1 million and $4.36 million last season, but their red circles denote far worse shot-based metrics than Hickey's:
The Islanders have been a surprisingly abundant source of quality, under-the-radar defensemen recently. Another free agent option could be his former Islanders teammate, Calvin de Haan. If he has fully recovered from shoulder surgery, de Haan could be another affordable free-agent target for top-four duty.
The All-Risk Team
Patrick Maroon, LW
Predicted contract: Four years, $5.3 million per year
Expected value: minus-28.4 goals (over four years)
Age: 30
Spending so much time playing with Connor McDavid, Maroon's value may have escalated beyond what is warranted.
It's certainly possible that Maroon will continue to average 0.58 points per game without McDavid, instead of falling back to his previous mark of 0.39, but even that higher scoring rate wouldn't justify the steep pay increase projected for this summer.
He's not alone in being a risky buy at left wing. There's also the possibility that the Kings' recent investment in Ilya Kovalchuk could backfire. Kovalchuk led the KHL in scoring last season, but he is 35 years old, his scoring totals were virtually identical to Thomas Vanek's in his final three NHL seasons from 2010-11 to 2012-13, and he carries a significant downside risk at $6.25 million per year for the next three years.
Tyler Bozak, C
Predicted contract: Three years, $4.4 million per year
Expected value: minus-15.9 goals (over three years)
Age: 32
When a scoring-focused forward reaches 32 years old, and his scoring drops to 43 points in 81 games in relatively sheltered usage, the odds are against remaining in the lineup for three years, let alone in the top six.
The most recent examples of free agents like this include Derek Roy and Ales Hemsky, who were in a similar situation on July 1, 2014. While the former was signed to a one-year contract, the latter was signed to a three-year deal with an annual cap hit of $4 million. By Year 1, Hemsky was already out of the top six, was an occasional healthy scratch, and fell to 32 points in 76 games. Any team who signs Bozak to a comparable contract this summer will be taking a similar risk.
Given that he is likely to sign a seven- or eight-year deal with an annual cap hit in excess of $10 million, there's a strong possibility that John Tavares will actually sign the riskiest contract of the summer. However, there is also a good chance that Tavares will make his new team an instant contender for the Stanley Cup. Lacking anything near that kind of upside, we went with Bozak on the All-Risk Team instead.
David Perron, RW
Predicted contract: Four years, $6.7 million per year
Expected value: minus-40.8 goals (over four years)
Age: 30
With so many players setting career highs for the miracle Vegas Golden Knights last season, there are bound to be a few contract offers driven too high by recency bias. Of them, the riskiest investment might be in Perron, who set a career high of 66 points, and whose 50 assists were tied for 26th in the NHL.
Absent an explanation for his sudden success in his age-29 season, the safest assumption is that Perron will return to his previous career average of 0.58 points per game in a new environment, which is 47.5 points over 82 games. While that may be an acceptable level of output at his previous cap hit of $3.75 million, it may prove to be a disappointment on the significantly more expensive deal that is projected for this summer.
John Carlson, D
New contract: Eight years, $8 million per year
Expected value: minus-27.9 goals (over eight years)
Age: 28
Nothing leads to regrettable contracts more than Stanley Cup success. Swept up in the glow of the aftermath, it's not unusual for front offices to offer far more than they otherwise would have.
Yes, Carlson led NHL defensemen with 68 points in 82 games last season, but it was only the second time he has scored 40 points or more in a season. How much of that scoring will he retain if circumstances change around him down the road? As for his shot-based metrics, it was only the first time in the past five seasons that he was in positive territory relative to his teammates.
Carlson joins P.K. Subban as the NHL's $8 million-per-season defensemen, with Oliver Ekman-Larsson -- and presumably Erik Karlsson and Drew Doughty -- joining them in 2019-20.
Jack Johnson, D
Predicted contract: One year, $2.6 million per year
Expected value: minus-1.1 goal
Age: 31
If you go with the projected contract cited above, then Johnson could prove to be a perfectly capable No. 4 defenseman next season, much as he was in Columbus playing with veteran David Savard upon the arrival of Seth Jones and Zach Werenski to handle first-pairing duties.
However, there's speculation that Johnson wants to return to a No. 1 role, where he once absolutely bombed in a fashion similar to Buffalo's Rasmus Ristolainen in 2017-18. Since the point when data is first available (2009-10), Johnson has a Corsi differential of minus-824, and the Blue Jackets' share of shot attempts has fallen from 51.2 percent to 48 when he's been on the ice at 5-on-5.
Despite these results, there are rumors that there are teams willing to oblige him with that No. 1 role, which may come with a multi-year deal with an annual cap hit of about $6 million. If so, it may mark a new regrettable high point for the recent free agent hysteria over mediocre fourth defensemen.
Methodology
To build these two lineups, we used the team-building model described in the first chapter of Stat Shot as a framework. First, it captures a player's value relative to a replacement-level player using a single metric, which is calculated using a weighted average over the past three seasons, and then regressed to the mean to remove the impact of random variation. In this analysis, Corsica Hockey's version of Wins Above Replacement was used for forwards, and Chace McCallum's version was used for defensemen. Goalies were not included.
Then, the model incorporates an aging curve to account for a player's improvement toward their prime, and their subsequent decline later in their careers.
Lastly, each player's results are converted from wins and goals into dollars, and they are evaluated relative to the cap space their contracts require. In this regard, Matt Cane's model was used to predict the term and annual cap hit for each of this year's unrestricted free agents, aside from John Carlson, who has already been re-signed by the Capitals.
With the added benefit of player usage charts, we were able to place this information into the proper context, and make manual adjustments based on how players were used in the past, and how they might be deployed in the future.