You should expect a pitcher to be "worse" in the postseason than the regular season. He is pitching every game against good teams instead of a mixture of good and bad teams.

Kershaw may be the worst, but Pedro Martinez, Greg Maddux and Randy Johnson all were worse in the postseason than regular season, just to pick a few. When picking for one game, I want the guy who has done it, Matty, over the one we don't know, Wajo. Johnson may have been great if given the opportunity to pitch World Series in his prime, but Matty was great in the World Series. Some players choke under pressure, such as Kershaw, others perform better. Matty was one who pitched better in the spotlight.

No question
 

Addie Joss

Walter, and all I need is one run.

After that Alexander, Walsh, and Bender.

Matty was a great pitcher, but he also lost some big games, and Waddell was too erratic. I'd consider Brown over either of them, actually.

Mathewson's post season record was 5-5, just for context. He was 2-5 after his incomparable '05 series.

He had a great World Series ERA of under 1, but he did lose the 1908 "playoff" game to Brown, and the final game of the 1912 Series, so when I think of a guy to win a big game, he's not at the top of my list, despite his obvious greatness and general dependability.

He gave up less than one run per nine innings. Is it his fault that he didn't get support at the bat or in the field? He was 1-5 in games that he didn't shut out the opponent.
In 1912, he pitched 3 complete games, giving up 3 earned runs in 28.2 innings, but went 0-2 because his defense allowed 8 unearned runs. In the deciding game, Matty had the Giants in position to win, but a dropped fly and dropped pop up, cost the Giants the game. Over his career, his defense gave up as many unearned runs, 11 as Matty gave up earned ones.

Hey, you just pretty much described Walter Johnson's career. ;)

Matty had a 1-run lead going into the bottom of the 10th inning of the final game. With one out, all he has to do is take charge and either catch Speaker's pop foul himself, or do the logical thing and call for Merkle to take it. Instead he called for Meyers (possibly the slowest-footed player in baseball) and Chief couldn't quite get to it. For Merkle or Matty it would've been an easy out. Speaker then supposedly calls out to Matty something like: "You just called for the wrong man and now it's going to cost you this ballgame," before singling in the tying run and advancing the eventual winning run to third.

That and the famous matchup with Brown at the end of the 1908 season were two huge do-or-die games Matty lost.

Ed Cicote because at least if lose the game we will make money

Matty's biggest mistake in that game came on the previous hitter. He walked the light-hitting Steve Yerkes, putting the winning run on base, and bringing up Speaker (who hit .383 that year).

Excellent point! Matty and his great control missed with 4 pitches to walk the guy ahead of Speaker, who turned out to be the winning run.

From 1905 through 1916, which blankets the T206 era, there were 4 do-or-die games where the Giants needed to win to survive. Matty lost 3 of them - the final games that lost the 1912 and 1913 World Series, and the final game that lost the 1908 pennant.

Ames lost the last game of the 1911 Series, Game 6, after Matty won Game 1 and lost Games 3 and 4...

It would be Rube Marquard, no doubt.

Walter Johnson, of course! BTW, 4 of the runs off WaJo in game 7 of the 1925 W.S. were unearned, due to errors resulting from the sloppy condition of the field.
Val

Post season records, for the most part, don't tell you very much. There just aren't enough games to be able to sort the signal from the noise. There's a lot of luck in baseball, and it takes lots of games to be able to figure out what is the effect of luck and what is really under the player's control. If you want to take them into consideration, combine them with regular season performance.

Raw WAR numbers don't help here, since they could reflect differences in the number of innings pitched (and we're only interested in one game). But something like WAR/games started might be helpful.

WaJo has 0.23 WAR per start.
Matty has 0.17 WAR per start.

I'll take Johnson.

Matty was great and all, but he tends to be over rated. He wasn't as good of a pitcher as Pete Alexander: they had identical ERA+s, Pete pitched 400 more innings, and has a significant lead in WAR. And both Matty and Alexander are a big step behind WaJo.

Smoky Joe Wood in 1912, but any other year I would say Mr. Johnson.

Oh to be at Fenway on Sept. 6, 1912!