Whether it's the choice of injury replacements, depth players or deployment of the special teams, all four teams in the conference finals are faced with at least one key lineup decision. Here's a look at each one and how the underlying numbers suggest the teams proceed.
Eastern Conference final
When Pittsburgh lost to Washington in the second round, it had nothing to do with the deployment of the Penguins' top lines. Sidney Crosby scored eight points to climb into a first-place tie with linemate Jake Guentzel at 21 points this postseason, and the power play scored on five of its 19 opportunities (26.3 percent). If they could go back and deploy their lineup differently, any changes would involve depth lines.
Learning from Pittsburgh's experience, Tampa Bay's toughest decision is whether to adjust its depth lines by reinserting Cory Conacher into the lineup. Even at 5-foot-8, Conacher is a physical player who can crash the net, and he was a tremendous force for the Syracuse Crunch in last year's AHL playoffs, leading the team with 28 points in 22 games.
Tampa Bay's fourth line is currently composed of veteran Chris Kunitz, center Cedric Paquette and Ryan Callahan, who was briefly replaced by Conacher when Callahan missed two games with a shoulder injury. They have played very well, but have scored just one goal in 10 games. Conacher is capable of giving that line more offensive bite: He has 40 points in 82 career regular-season games with the Lightning, 228 points in 240 AHL games and 52 points in 48 games for Bern of the Swiss National League A in 2015-16.
To shake up the depth lines, other possibilities include Matthew Peca and Adam Erne, who recently returned to the ice after missing the last six games of the regular season with a lower-body injury.
Nicklas Backstrom missed Game 6 of Washington's second-round series against the Penguins with an injured right hand, and his status for Game 1 of the conference final is uncertain.
At even-strength, the Capitals lack the depth down the middle to replace him on the second line with anyone other than Lars Eller. Since Evgeny Kuznetsov is on the top line with Alex Ovechkin, and Jay Beagle is meant strictly for the defensive lines, there's no other option except rookie Travis Boyd, who would replace Eller on the third line.
Replacing Backstrom on the power play is where the Capitals have some flexibility. Washington leans heavily on its top unit of Backstrom, Ovechkin, Kuznetsov, John Carlson and T.J. Oshie with the man advantage and rarely uses its secondary unit. Backstrom is a critical component, with a three-year average of 6.91 points per 60 minutes in such situations, ranking fourth among those to play at least 200 minutes, according to Corsica Hockey.
In his absence, the Capitals still have Kuznetsov (6.12), Carlson (5.57), Ovechkin (4.84) and Oshie (4.15), but have no obvious choice to complete the unit. The next-highest-scoring player is defenseman Matt Niskanen (3.90), but the unit is built around having Ovechkin on the point, and Carlson is already on defense. Carlson's 10 power-play points are tied for second in the postseason.
Among forwards, that leaves Brett Connolly (3.53), Eller (2.68) and Alex Chiasson (1.76), but none of them have played even 200 minutes with the man advantage over the past three regular seasons combined. On the power play, the most experienced forward is Boyd, who has scored 21 goals and 49 assists on the power play in 215 career AHL games.
If the Capitals are going that route, then they may consider recalling Chris Bourque, who is one of the AHL's all-time leaders with 88 goals and 222 assists with the man advantage in 716 career games. He has five power-play points in 51 career NHL games, the last of which was played March 5, 2013.
Western Conference final
The most significant lineup adjustments the Jets may be considering are regarding their short-handed group. Through 12 games, they have allowed seven goals in 28 opportunities (75 percent penalty-kill percentage).
The responsibility for these goals has not been equally shared. No goals have been allowed when the team's top penalty-killing forwards, Adam Lowry and Brandon Tanev, have been on the ice for 19:11 and 19:06 minutes, respectively. In contrast, seven goals have been allowed when their top defensemen, Jacob Trouba (24:31) and Josh Morrissey (24:07), have been on the ice. That works out to a personal goals-against average of 17.13 and 17.42, respectively, per 60 minutes.
Against Vegas, the Jets may lean more toward Tyler Myers, who led the team with 212:52 short-handed minutes in the regular season, during which 22 goals were scored for an average of 6.20 goals allowed per 60 minutes. In the playoffs, the Jets have allowed one such goal in 18:18 minutes (3.28 average per 60 minutes). The possible return of Dmitry Kulikov, who averaged 6.14 before sustaining a back injury on March 8, might also give the team more options.
On May 5, the Golden Knights recalled 10 players and a goalie from the minors, which is on top of the five extra players and goalie that they already had. The most interesting decision will be which of these players to use up front.
Setting aside the top two lines, which are likely to remain untouched, and ignoring players without NHL experience, here are the 11 forwards from which the Knights can choose to build their third and fourth lines. The list includes William Carrier, whose status for Game 1 is uncertain.
While it's impossible to boil down a player's performance into a handful of numbers, the four that we have selected here can at least provide some context of how players were used and what the results have been in terms of scoring and shot-based metrics.
For example, at 5-on-5 over the past three seasons combined, Oscar Lindberg was deployed in the offensive zone rather than the defensive zone 58.33 percent of the time; his average opponent was assigned 28.14 percent of all available even-strength minutes; the team's shot-based metrics dropped by 0.09 percent when he was on the ice; and he averaged 1.51 points per 60 minutes, according to the calculations at Corsica Hockey. That makes Lindberg an obvious choice for inclusion in the lineup.
Another easy choice is the inclusion of Alex Tuch, who ranks second with 1.47 points per 60 minutes and third in increasing his team's share of shot attempts (by 1.52 percent).
There are rumors that Ryan Reaves is going to be included in the lineup at the expense of a player like Tomas Tatar, but these numbers demonstrate why that might be inefficient. Tatar's scoring rate of 1.44 points per 60 minutes ranks third, well ahead of Reaves, and he increased the team's share of shot attempts by 3.32 percent, which ranks second to Carrier (3.57). Reaves ranks last, as the team's share of shot attempts drops by 4.56 percent when he's on the ice, despite the lowest average quality of competition.
For even more extra scoring, the Golden Knights may consider longtime AHLer Ryan Carpenter and/or journeyman Brandon Pirri at center. They rank next in terms of scoring, and Pirri has respectable shot-based metrics. However, the Knights have been leaning on Cody Eakin and Pierre-Edouard Bellemare all season, both at even strength and when killing penalties, and they are unlikely to change course now. Instead, Carpenter and Pirri might contend for the vacant wing opening until Carrier returns to action.