Philadelphia Phillies Meeting Expectations Under Rob Thomson

The New York Yankees, Los Angeles Dodgers, Houston Astros, New York Mets, Atlanta Braves and St. Louis Cardinals. Those are only teams that have a better run differential than the Philadelphia Phillies after the first half of the season.

So what gives? Why are the Phillies not in a better position?

With a run differential estimated record of 52-40, the Phillies should be comfortable in a playoff spot. Instead, they barely cling to the third Wild Card.

The obvious reason for a club under-performing their run differential is luck. The Phillies are losing a lot of games by tight one-run margins, and when they win, they tend to blow out their opponents.

In one-run games, the Phillies are 10-15 and in games decided by more than five runs, they are 14-9.

The reason a team might consistently lose one-run games are usually small, needling issues on the fringes of the roster. Lack of late-game defensive replacements, high FIP for relievers, positional flexibility, and bench depth are all variables that can lead to a team under-performing their run differential. The Phillies don't exactly have those traits in abundance.

However, since interim manager Rob Thomson replaced Joe Girardi on June 3, some aspects have begun to improve, most notably in the bullpen.

Prior to Girardi's firing, Philadelphia's bullpen FIP was 3.90, 16th league-wide. Since that date, their FIP has improved to 3.50, which ranks ninth in the league.

If Girardi's firing could improve the bullpen by that much, could he also be the reason the Phillies are so far behind their expected win total?

The answer, unsurprisingly, is yes.

The day Joe Girardi was fired, the Phillies had a run differential of +1. That should translate to a win percentage of almost exactly .500, but the Phillies were 22-29 on that date, well below their expected total.

Since Rob Thomson took over, the Phillies have a run differential of +61 with 201 runs scored and 140 runs allowed. It's an extremely impressive scoring rate that translates to an expected winning percentage of .673 or a record of about 27-14.

Would you look at the that! Since Thomson took the reins, the Phillies have perfectly matched their expected production. They are 27-14 in that time. That's a better winning percentage than the Houston Astros have this season (.648).

Not only has Thomson brought about better performances out of his players, but clearly Girardi failed to put his players in positions to succeed and failed to manage his roster the way it was assembled to play.

Had Thomson started the year as Phillies manager, or anyone other than Girardi for that matter, it's very possible that the Phillies could be playing to—or perhaps even better than—their 52-40 expected record right now.

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