Things went pretty well on Opening Day for the Phillies on Monday. They won 11-1, Roy Halladay went 7 innings and struck out 9, Ryan Howard hit a 2-run homer and even Rule 5 pick David Herndon closed out the game with a scoreless inning in his first major league appearance. Jayson Stark wrote about Halladay, of course, but he also wrote about off-season acquisition Placido Polanco.
Polanco (right, head made even more monstrous for my own amusement) had a pretty good first day, too; he went 3-for-5 with 6 RBI and a run scored. His grand slam in the top of the 7th inning made it 11-1. But get this: Polanco had a negative WPA for the game. (Fangraphs has him at -.027, while Baseball-Reference has him at -.029.)
So how'd this happen? First, a quick primer: WPA, which became kind of trendy last season, stands for Win Probability Added. You know those fancy live win expectancy graphs on Fangraphs? Well, each play adds or subtracts from a team's chances (in percentage) of winning a game. So each player gets either a positive or negative WPA after each plate appearance. Add up all those plays for one player, and you get a guy's WPA for a game. (WPA is one of the simplest advanced stats, I think, unless I completely screwed this up. In which case it's the most complicated!)
Polanco's WPA was negative on Monday because he didn't do much when the game was close. He flied out to foul territory in right field in the first and grounded out with a runner on in the third. By the time he came to the plate in the fourth, the Phillies were up 4-1 and were already almost at 90 percent likely to win the game. When he capped the Phillies' five-run fourth with a sacrifice fly, Polanco actually recorded negative WPA for the play. When he hit his slam in the 7th, the Phils were already 99 percent likely to win.
Does this mean Polanco's day was worthless for the Phils? Of course not. Not that the Nationals were going to come back anyway, but a 10-run lead certainly made it more likely that Roy Halladay would get the rest of the day off after seven innings. And getting 6 RBI in the first game with a new club has to do wonders for Polanco's confidence (+1.029 Confidence Added!).
But I do think looking at WPA can teach us a lot about how strange this game is. With one swing, Ryan Howard accumulated more WPA than Polanco could get all game, even though the Phillies new third baseman hit a slam later in this one. What can we take from this? Situations matter. Luck matters. And sometimes 6 RBI might not be as impressive as 2 RBI, in a way.