In a spring training game on Feb. 27, Tommy Joseph started in left field for the Phillies. It was strange enough to see the stout first baseman in the outfield, but then something even stranger happened. In the top of the second inning, the Phillies made a pitching change. Tigers farmhand Victor Reyes, a switch-hitter, was due up and would be hitting from the left side. Joseph jogged over to right field and Collin Cowgill moved from right to left field. After Reyes struck out, the two outfielders again exchanged positions.

One of the compelling aspects of baseball is how the game continues to evolve. Some changes are obvious even to the untrained eye, like the home run explosion of the past couple of seasons or the infield shifting that began earlier this decade. Some changes are more subtle. For example, take the pitchout. Did you know the pitchout is essentially dead? Last season, National League teams threw just 59 pitchouts. The Nationals under Dusty Baker had three. Back in 1996 when he was managing the Giants, Baker called 96 pitchouts. Nobody throws pitchouts anymore. Why waste a pitch?

So maybe what we’ll call the Gabe Kapler outfield shift will be the beginning of a revolution. In the specific case of Joseph, even if he makes the Phillies' roster, it’s hard to envision a scenario in which he ends up in the outfield, although it’s possible the Phillies will also consider the shift with Rhys Hoskins, a converted first baseman with little experience in left field.

As Matt Gelb outlined in the The Athletic, the specific maneuver for Reyes was discussed before the game. The Phillies’ spray charts indicated Reyes was more likely to hit the ball to left field in the air, so they moved their better defensive outfielder there. From Gelb’s piece:

“I think it'll happen a lot,” Cowgill said. “I think it's great. I love it.”

The Phillies have used the Grapefruit League games to implement their aggressive outfield shifting for every batter, based on spray charts. But they will go beyond that, flipping players across the field when the numbers tell them it is wisest.

That is why Hoskins, who will move from first base to left field this season, has begun some light work in right field. The Phillies hope Hoskins can be a passable defender in left field. But they know he lacks range and instincts because it is a new position for him. He will be their worst outfield defender. So Hoskins expects some mid-inning position changes when the data is clear.

“I think if it goes the way they're hoping, I don't see why not,” Hoskins said. “Yeah. If we have a chance to get more outs in a big situation, I don't see why not.”

So there appears to be some buy-in from Phillies players, at least for now, although I haven’t seen evidence of them trying it again so far this spring. The bigger question: Is it worth it?

Part of the complexity of making this move is that while most ground balls are pulled, making the infield shift a more obvious decision, balls to the outfield are sprayed more equally. Here are the 2017 breakdowns for fly balls and outfield line drives from ESPN Stats & Information:

Left-handed hitters

• Left field: 37.1 percent

• Center field: 34.5 percent

• Right field: 28.4 percent

• Far left: 22.5 percent

• Far right: 16.4 percent

Right-handed hitters

• Left field: 29.7

• Center field: 34.8

• Right field: 35.5

• Far left: 17.9

• Far right: 21.4

For the generic hitter, there is no reason to make a change. Obviously, individual hitters have more extreme tendencies. Even then, only five qualified regulars last year hit at least 50 percent of their fly balls and outfield line drives to the opposite field -- Joe Mauer, DJ LeMahieu, David Freese, Eric Hosmer and Christian Yelich. Freese pulled just 3.4 percent of his fly balls and outfield line drives, but since he’s a right-handed batter, that means his balls would be going -- in the Phillies’ case -- to the better outfielder. Hosmer is definitely a batter a you might consider the Kapler Shift for:

What’s the potential value in something like this? Russell Carleton of Baseball Prospectus studied this in a piece last year. He was writing about using a pitcher in the outfield for a batter (and then bringing the pitcher back in to pitch), but his math still applies. He wrote:

From 2012-2016, only 8.7 percent of plate appearances ended with either a fly ball or a line drive that the left fielder eventually fielded (whether to catch it or pick it up when it stopped rolling). We also know that most fly balls fall into either the category of “any competent human with a glove on his hand could make that catch” or “no one was going to get to that.” The spread between good fielders and bad is generally on a small subsample of fly balls per year.

I’ve estimated that the difference between an average left fielder and a really bad one is about .02 runs per inning, and we’re not talking about a full inning here.

Of course, the Phillies have their own team of analysts and it’s possible they’ve come up with a different number on the potential runs that could be saved, depending on how often the tactic is employed. If it’s .02 runs, it hardly seems worth the effort, especially after considering the mitigating circumstances: Do you really want to make Hoskins run back and forth throughout a game? Does it affect the pitcher’s rhythm? For the love of god, what about pace of play?

Still, it’s a fascinating idea. Maybe it saves the Phillies a few outs a year -- and maybe one of those outs saves a couple of runs in a key moment. You never know.

By the way, while I don’t know of another team trying this experiment (except a couple of times when a pitcher ended up in the outfield in an extra-inning game), the 1959 Indians tried something similar in the infield. Check out these box scores from June 27 and June 28.

If you click, you can see that Woodie Held’s position is listed as SS-2B-SS-2B-SS-2B-SS-2B-SS-2B-SS-2B-SS-2B-SS-2B-SS-2B. Same thing with Granny Hamner. Manager Joe Gordon was moving Held and Hamner based on whether the batter was a lefty or righty, playing the younger Held on the pull side.

So why was the experiment abandoned after two games? As it turns out, there were only four games where Held started at shortstop and Hamner at second base, June 25 through June 28. In the first game, there were no changes. In the second game, there was one change (my guess is for Ted Williams). In the next two games, also against the Red Sox, Gordon went wild. But Hamner played just a few more games the rest of the season and started just once more (at third base), so he abandoned the player more than the experiment.

Will Kapler pull his own version of Gordon’s exchange? Stay tuned.