Picture this: you are an MLB pitcher, finishing your warm-up routine in the bullpen while your team, as visitors, is batting for the first time in the game you are going to be the starter. Between throws, you take a peek at the field and you see movement around the bases; your playmates are getting some hits and are about to get some runs on the scoreboard. In fact, a few minutes later, they get a couple of runs before surrendering the final out of the top of the first inning.
Good. You feel more confident now and you will take advantage of this. You are going to win today.
But, are you? Is it true, as the old thinking goes, that when a pitcher gets early backup they pitch better as they are more confident? Or that’s just baseless nonsense? Let’s find out.
In this shortened season, 162 times happened exactly that: visiting pitchers saw their teams score in their first time at bat: 68 times they scored 1 run, 53 two runs, 22 three runs, 14 four runs, 2 times five and 6 runs each and 1 time seven runs.
So, how did they perform after that? They should have done better than starters in general, right?
In that respect, starters in general that were eligible for a W (pitching at least 5 innings) had the following results regarding W-L decisions:
Starting pitchers, who went 5 IP or more, got the Win 45% of the times, losing 23% and leaving without decision 32% of those opportunities for a 55% combined Loss/No Decision; ERA for this group was 2.94, K/9 8.91, and BB/9 2.45. This will be our comparison group as we are assuming that pitchers with an early back up should be bound to pitch longer in the game, at least long enough to be eligible for the W.
In the 162 instances in which the visiting team scored 1 or more runs opening the game, giving their SP some early support, 101 of those times the SPs went to throw 5 or more innings and 62 times they got the Win, so 100 times either they lost or did not factor in the decision.
This is an eye-opener: those pitchers with early run support won fewer games (38%), percentage-wise, than the SPs in regular starts with 5 or more IP. The difference is short enough to consider it definitive, especially adding to the fact that the ERA for this group was significantly smaller, 2.06, so at least from the pitcher’s side, there was an impact. For the limited sample set of this short season, this is not an ideal situation to get any conclusion from but should raise interest for any further inquiries on the matter.
So, which pitchers got early back up most times? We can check that in this list:
Pitching for the Dodgers is kind of sweet, isn’t it? 40% of his starts, Clayton Kershaw started the game pitching with the cool advantage of having early run support. Trailing Kershaw’s four, Snell, Singer, Cole, Canning, Berríos, Gray and Howard had 3 each and then 25 other pitchers with 2.
How did that group fare in those opportunities? Some pitchers took more advantage than others, as Cole, Javier, Anderson, Gonzales, Scherzer, Bauer, Glasnow, and Eflin each won all of the multiple chances they got; Kershaw won 3 out of 4 and Snell 2 out of 3. But those were outliers as a whole they won 44% of the time, practically the same as the pitchers that went 5+ IP in general.
Keeping in mind the small sample, I find no evidence that getting a first-inning advantage increases the odds for a visiting SP to get a W in that type of games.
All data used was taken from https://stathead.com/baseball/, https://www.fangraphs.com/, https://baseballsavant.mlb.com/, and/or https://www.baseball-reference.com/, unless otherwise stated differently. pCRA data was taken from this Tableau, maintained by its creator Connor Kurcon.