Chan Ho Park's Earned Runs Allowed on April 23, 1999

Question

I saw a crazy stat today where Fernando Tatis Sr. hit two grand slams in a single inning, and crazily enough both off of Chan Ho Park, on April 23, 1999 in a game between the St. Louis Cardinals and the L.A. Dodgers, something that has never been done before or since.

Baseball-Reference.com records Park as pitching 2.2 innings that day and giving up 11 runs. However, only 6 of them were counted as earned.

Pitching                IP  H  R ER BB SO HR   ERA
Chan Ho Park L (1-2)   2.2  8 11  6  3  2  3  7.32
Carlos Perez           4.1  3  1  1  0  4  1  7.06
Jeff Kubenka             2  0  0  0  2  1  0 12.27
Team Totals              9 11 12  7  5  7  4  7.00

Provided by Baseball-Reference.com: View Original Table

I don't know what the official rules on this were back in 1999, but I can't imagine they changed much.

9.16 Earned Runs and Runs Allowed

An earned run is a run for which a pitcher is held accountable. In determining earned runs, the Official Scorer shall reconstruct the inning without the errors (which exclude catcher’s interference) and passed balls, giving the benefit of the doubt always to the pitcher in determining which bases would have been reached by runners had there been errorless play.

I get that it depends on the situation, but to me, given that at least 8 of the runs (in just this one inning) came off Tatis' two grand slams and not as a result of any error (i.e. these were legitimate hits), how is it that Park isn't charged at least 8 earned runs as well?

Answer 1

There was no error on the home run plays, but there was an error in between. Once you get to a point in the inning where you would have had 3 outs with errorless play, all further runs are considered unearned.

When McGuire flied out for the second out, plus Karros's error, there "should have" been 3 outs. There were 7 runs at that point, 6 earned and 1 unearned.

All runs later in the inning (in this case, all the runs from Tatis's grand slam) are also unearned.

MLB Rules 9.16

In determining earned runs, the Official Scorer shall reconstruct the inning without the errors (which exclude catcher’s interference) and passed balls, giving the benefit of the doubt always to the pitcher in determining which bases would have been reached by runners had there been errorless play.

...

9.16(a) Comment 3 confirms that home runs may be unearned due to earlier errors in the inning.

With two out, Abel reaches first on an error by the shortstop in misplaying a ground ball. Baker hits a home run. Charlie strikes out. Two runs have scored, but none is earned, because Abel’s at-bat should have been the third out of the inning, as reconstructed without the error.

Answer 2

This is where play-by-play gives us context. Let's take a look at Baseball Reference.

For the first home run, these are all earned runs.

Inn	Score	Out	RoB	Pit(cnt)	R/O	@Bat	Batter	Pitcher	wWPA	wWE	Play Description
t3	0-2	0	---	2,(1-0)		STL	Darren Bragg	Chan Ho Park	4%	33%	Single to RF (Ground Ball thru 2B-1B)
t3	0-2	0	1--	5,(2-2)		STL	Edgar Renteria	Chan Ho Park	6%	39%	Hit By Pitch; Bragg to 2B
t3	0-2	0	12-	2,(0-1)		STL	Mark McGwire	Chan Ho Park	9%	48%	Single to RF (Line Drive to Deep 2B-1B); Bragg to 3B; Renteria to 2B
t3	0-2	0	123	3,(2-0)	RRRR	STL	Fernando Tatís	Chan Ho Park	23%	71%	Home Run (Fly Ball to Deep LF); Bragg Scores; Renteria Scores; McGwire Scores

For the second home run, there is an error. This dispels the claim that "at least 8 of the runs (in just this one inning) came off Tatis' two grand slams and not as a result of any error" and further elaborated in this answer.

Inn	Score	Out	RoB	Pit(cnt)	R/O	@Bat	Batter	Pitcher	wWPA	wWE	Play Description
t3	5-2	1	123	3,(1-1)	R	STL	Darren Bragg	Chan Ho Park	5%	90%	Reached on E3 (throw) (Ground Ball to Weak 2B-1B); Polanco Scores/No RBI; McEwing to 3B; Jimenez to 2B
t3	6-2	1	123	5,(2-2)	R	STL	Edgar Renteria	Chan Ho Park	4%	93%	Single to RF (Line Drive to Short RF Line); McEwing Scores/unER; Jimenez to 3B; Bragg to 2B
t3	7-2	1	123	4,(1-2)	O	STL	Mark McGwire	Chan Ho Park	-2%	91%	Flyball: RF
t3	7-2	2	123	6,(3-2)	RRRR	STL	Fernando Tatís	Chan Ho Park	7%	98%	Home Run (Fly Ball); Jimenez Scores/unER; Bragg Scores/unER; Renteria Scores/unER; Tatis Scores/unER