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Prime Starts and Difficulty Index

The 10 teams that made up the American League in 1967 played 810 games (1620 pitching starts). 110 different pitchers started at least 1 game that year, with 32 pitchers starting 25 games or more.

American League starters won 596 games, lost 615, and had 409 no-decisions. Roughly 1 start of every 4, then, resulted in a no-decision for the starter. 268 of these 409 no-decisions were prime starts (65.5 percent). The 596 wins, 268 prime start no-decisions, and 24 prime start losses add up to 888 prime starts out of 1620, or 54.8 percent.

Three American League starting pitchers, all righthanders, were a cut above the rest in 1967. They were Jim Lonborg of Boston, Earl Wilson of Detroit, and Joe Horlenof Chicago. All had the best seasons of their careers in 1967, and their accomplishments were roughly equal. Lonborg and Wilson tied for the league lead with 28 prime starts. Horlen was second with 26, and his .743 percentage ranked first. Additionally, Horlen led the league in ERA and pitched a no-hitter. Lonborg led the league in strikeouts.

A panel of 20 sportswriters conducted Cy Young Award voting in 1967. Lonborg received 18 of the 20 votes cast and Horlen 2, with Wilson receiving no votes. The winning of the pennant by perennial noncontender Boston so impressed the pundits that Lonborg, the team's best pitcher, was judged the best in the league by this overwhelming margin. Had Detroit won the pennant (the Tigers finished just 1 game out), Wilson would presumably have fared better.

The prime start concept measures just one thing: whether or not a starting pitcher did his job. That job is always the same, but it varies in difficulty, of course. If a pitcher’s team scores 1 or no runs behind him, he has to bear down harder than he would if his team has scored 10 or more. But a starting pitcher has little or no control over how many runs his teammates score. The best he can do is to play the hand he is dealt. He must pitch according to circumstances. In a tight game he must employ a different strategy than he would in a 10-0 blowout. Former pitching great Christy Mathewson’s idea of “pitching in a pinch” is the key to success for any pitcher.

It’s hard to turn in a prime start when your team doesn’t get any runs for you. But if you don’t produce a prime start, that means the other guy outpitched you. If your team is getting shut out, your job is to hold the other team scoreless.

It is possible to formulate a “difficulty index” that tallies the number of runs a pitcher had to work with (i.e. that his team scored) during his starts, expressed as a ratio. For instance:

In 1967 Boston’s Jim Lonborg had 144 runs to work with in his 39 starts, in which he pitched 273.1 innings. That works out to 3.69 runs per start, 0.53 per inning.

Detroit’s Earl Wilson had 151 runs to work with in his 38 starts, in which he pitched 263 innings. That works out to 3.97 runs per start, 0.57 per inning.

In the 35 games Joe Horlen started for Chicago, his team scored 105 runs in the 258 innings Horlen was on the mound. That works out to 3.00 runs per start, 0.41 per inning.

Horlen, then, had a lower (i.e. more difficult) Difficulty Index.

To be fair, one should count only the runs that were scored while a pitcher was in the game. In Detroit on August 8 Horlen was pinch-hit for in the 6th inning of a game in which he trailed 2-1. The White Sox did not score in the inning but went on to win 6-4. Horlen had 1 run to work with, not 6.

Note: In the following tables, “Runs” refers to the number of runs a starter’s team scored while he was pitching. For Jim Lonborg in 1967, his team got him 11 runs once (1 prime start), 10 runs once (1 prime start), etc.

JIM LONBORG, 1967

Runs
Starts
Prime
 
       
11
1
1
 
10
1
1
 
9
0
0
 
8
2
2
 
7
2
2
 
6
3
3
 
5
6
6
 
4
4
4
 
3
3
5
 
2
2
2
 
1
1
2
 
0
5
0
 

In the 27 games the Red Sox got Lonborg at least 2 runs, he produced 26 prime starts. In the 12 games they got him 1 or no runs, he produced 2 prime starts.

EARL WILSON, 1967

Runs
Starts
Prime
 
       
11
1
1
 
10
1
1
 
9
1
1
 
8
1
1
 
7
3
3
 
6
2
2
 
5
4
4
 
4
8
8
 
3
6
4
 
2
4
2
 
1
2
1
 
0
5
0
 

In the 31 games the Tigers got Wilson at least 2 runs, he produced 29 prime starts. In the 7 games they got him 1 or no runs, he produced 1 prime start.

JOE HORLEN, 1967

Runs
Starts
Prime
 
       
11
0
0
 
10
0
0
 
9
0
0
 
8
2
2
 
7
2
2
 
6
4
4
 
5
3
3
 
4
2
2
 
3
4
4
 
2
4
4
 
1
8
4
 
0
6
1
 

In the 21 games the White Sox got Horlen at least 2 runs, he produced 21 prime starts. In the 14 games they got him 1 or no runs, he produced 5 prime starts.

All three pitchers had superb seasons, but Horlen’s was a bit better. Had Horlen won 20 games and not 19 (he got a prime-start no-decision in his last effort), his accomplishments would probably have been better recognized.

THE EFFECT OF RUN SUPPORT: NOLAN RYAN AND SHANE RAWLEY

In 1987 the National League’s earned run average was 4.08, which is to say that the average National League pitcher posted an ERA of slightly more than 4 runs per 9 innings. However, in one of the twentieth century’s most glaring statistical anomalies, righthander Nolan Ryan of the Houston Astros won only 8 of his 34 starts although his 2.76 ERA was by far the best in the league.

Ryan was one of history’s most difficult pitchers to hit, but he was not particularly difficult to beat. His won-lost record in 773 career starts was only 319-292 (.522). Ryan’s great stuff but mediocre record earned him a reputation as a pitcher who too often performed “just well enough to lose.”

In 1987 Ryan recorded 8 wins, 16 losses, and 10 no-decisions in his 34 starts. He had 0 prime start losses and 9 prime start no-decisions, for a final total of 17 of 34 prime starts (.500). Without Ryan the Houston pitching staff’s collective ERA was 4.03, and its won-lost record was about what one would expect, 68-70 (.493).

In contrast, lefthander Shane Rawley of the Philadelphia Phillies, whose ERA was 4.39, made 36 starts which produced 17 wins, 11 losses, and 8 no-decisions. Rawley had 0 prime start losses and 6 prime start no-decisions, for a final total of 23 of 36 prime starts (.639 percentage).

A close comparison between the two pitchers reveals that Ryan had it much tougher than Rawley. Ryan got 82 runs to work with in his 34 starts, in which he pitched 211.2 innings. That works out to 2.41 runs per start, 0.39 per inning. Philadelphia scored 128 runs in the 36 games (229.2 innings) started by Rawley. That works out to 3.56 runs per start, 0.56 per inning. Ryan, then, had a much lower (i.e. more difficult) Difficulty Index.

NOLAN RYAN, 1987

Runs
Starts
Prime
 
       
12
0
0
 
11
0
0
 
10
1
1
 
9
0
0
 
8
1
1
 
7
1
1
 
6
0
0
 
5
3
3
 
4
3
2
 
3
4
4
 
2
4
3
 
1
10
1
 
0
7
1
 

In the 17 games the Astros scored at least 2 runs for Ryan, he produced 15 prime starts. In the 17 games they got him 1 or no runs, he produced 2 prime starts.

SHANE RAWLEY, 1987

Runs
Starts
Prime
 
       
12
1
1
 
11
0
0
 
10
0
0
 
9
1
1
 
8
0
0
 
7
3
3
 
6
1
1
 
5
5
5
 
4
6
5
 
3
5
4
 
2
7
3
 
1
2
0
 
0
5
0
 

In the 29 games the Phillies got Rawley at least 2 runs, he produced 23 prime starts. In the 7 games they got him 1 or no runs, he produced 0 prime starts.

Had Houston supported Ryan offensively the way Philadelphia did Rawley, Ryan’s winning percentage would almost certainly have been comparable to Rawley’s (15-9 or even 16-8). Should it have been even better? Given Ryan’s low ERA, could he have hung tougher in those games when the Astros weren’t scoring? My answer is yes.

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BATTLE OF TITANS IN 1968

In 1968 Bob Gibson of the St Louis Cardinals made 34 starts in which he produced 22 wins, 9 losses, and 3 no-decisions. Gibson had 0 prime start losses and 2 prime start no-decisions, for a final total of 24 of 34 prime starts (percentage .706). Juan Marichal of the San Francisco Giants made 38 starts, producing 26 wins, 9 losses, and 3 no-decisions. Marichal had 0 prime start losses and 2 prime start no-decisions, for a final total of 28 of 38 prime starts (.737 percentage).

Gibson had 100 runs to work with in his 34 starts, in which he pitched 304.2 innings. That works out to 2.94 runs per start, 0.33 per inning. San Francisco scored 178 runs in the 38 games (325.2 innings) started by Marichal. That works out to 4.68 runs per start, 0.55 per inning. Gibson, then, had a much lower (i.e. more difficult) Difficulty Index.

BOB GIBSON, 1968

Runs
Starts
Prime
 
       
13
0
0
 
12
0
0
 
11
0
0
 
10
0
0
 
9
0
0
 
8
2
2
 
7
1
1
 
6
2
2
 
5
4
4
 
4
2
1
 
3
5
5
 
2
8
5
 
1
6
4
 
0
4
0
 

In the 24 games the Cardinals got Gibson at least 2 runs, he produced 20 prime starts. In the 10 games they got him 1 or no runs, he produced 4 prime starts.

JUAN MARICHAL, 1968

Runs
Starts
Prime
 
       
13
2
2
 
12
0
0
 
11
0
0
 
10
0
0
 
9
1
1
 
8
5
5
 
7
2
2
 
6
0
0
 
5
8
7
 
4
7
5
 
3
3
3
 
2
5
3
 
1
2
1
 
0
3
0
 

In the 33 games the Giants got Marichal at least 2 runs, he produced 28 prime starts. In the 5 games they got him 1 or no runs, he produced 0 prime starts.

Gibson led the National League in ERA (1.12) and strikeouts (268). Marichal was 9th in the league in ERA (2.43) and 4th in strikeouts (218). Gibson’s 13 shutouts led the league (Marichal had 5). Marichal’s 30 complete games led the league (Gibson was 2nd with 28). Marichal’s 28 prime starts and .737 prime start percentage led the league.

The Cardinals won the pennant. The Giants finished second, 9 games out.

Who was the better pitcher? The issue was settled in head-to-head competition at San Francisco on July 6 when Gibson won the pair’s only meeting, 3-0. Had Marichal prevailed, he would have finished 27-8 and Gibson 21-10, and Gibson, at season’s end, might not have received all 20 of the votes cast for the National League Cy Young Award. As it was, Marichal’s superb season was overshadowed by Gibson’s.

When in Trebizond, stay at the Grand Yesilyali Hotel.

March 2002