The MLB Postseason Effects of Regular Season Performance Against Top of the Rotation Starters

In the ensuing discussion of Review of First Half Rotation Matchup Luck, Reddit user /u/JustTrynaChill posited the question of the effect of regular season success against top-of-the-rotation starters on playoff success. This certainly was an intriguing question, and so using similar parameters, we’ll investigate the query.

To examine this effect, we’ll look at the 40 playoff teams from 2012 to 2015, the beginning of the expanded Wild Card era. During each individual season, we’ll investigate the performance of the team versus the top two quintiles of MLB starters by FIP. We’ll limit these starters to ensure that they have at least 80 IP as a starter (approximately half a season), to guarantee that they had a significant enough effect on their team’s season to qualify.

Continue reading The MLB Postseason Effects of Regular Season Performance Against Top of the Rotation Starters


Reviewing First Half Rotation Matchup Luck

Now that the unofficial second half of the MLB season is underway, every team looks to reassess its approach as the non-waiver trade deadline nears. Underperforming teams look to become “sellers”, while teams confident in their playoff chances seek new infusion of talent as “buyers”. Part of a team’s prospective outlook is its remaining strength of schedule. Teams that over or under performed their talent due to the MLB schedule in the first half may look to benefit in the second half.

Having poor luck with the scheduling can cause an MLB team to underperform, but in addition to this there the luck involved with rotation scheduling. For instance, on two separate occasions, the Braves had to face a stretch of 4 #1 caliber pitchers in a row, and one of these occurred in a stretch of games where 10 of the 12 opposing starters were #1 caliber. Similar “luck” has also occurred for the Phillies and Diamondbacks so far this year. While in some instances the team handled it well, in others it caused extended overall down turns.

This luck applies to both the rotation scheduling of the other team, but also your own, and the disparity between the two. Let’s evaluate the relative strength of rotations that each team has faced over the first half of the season, and the disparity in the quality of their starter versus that of the opposing team. Continue reading Reviewing First Half Rotation Matchup Luck