Oakland Athletics shortstop Marcus Semien has committed 27 errors entering Thursday's game, an amazingly high total for this stage of the season. Ian Desmond led shortstops last season with 24 errors. Starlin Castro, with 29 in 2011, was the last shortstop with more. Desmond, with 34 in 2010, was the last with 30. The A's appear determined to keep Semien there, so he seems like a lock to surpass those totals. The last shortstop with 40 errors was Jose Offerman, with 42 in 1992. His fielding percentage that year was .935; Semien's fielding percentage is .925.

So how much have Semien's errors hurt the A's? After all, they're 7-22 in one-run games, a reason they're 39-48 even though they have outscored their opponents by 49 runs. They have allowed 42 unearned runs. Only the San Diego Padres (46) have allowed more. Surely, Semien's errors are a big reason for that.

We'll check out every error he's made, but here's a remarkable thing to consider: Baseball Info Solutions has Semien with +1 Defensive Run Saved. In other words, a league-average shortstop, even with all the errors. That's the same rating that Asdrubal Cabrera has, who has made just two errors. (UZR is more harsh, with Semien at -14 runs, second-worst in the majors to Desmond.)

I also noticed this: The A's actually have a better record when Semien makes an error than when he doesn't. He's made an error in 23 different games; the A's are 12-11 in those games. So they're 10 games under .500 when he doesn't make an error.

Here are Semien's 27 errors -- descriptions come from Baseball Info Solutions -- and how they affected the A's that inning.

1. April 8: Groundball through infielder.

Rangers didn't score in the inning. No damage.

2. April 11: Failing to catch the throw from an infielder.

This was huge. With two outs in the eighth inning after the error, Nelson Cruz hit a three-run homer. Three unearned runs. The Mariners would win 5-4 in 11 innings.

3. April 12: Bad throw.

Mariners didn't score in the inning.

4. April 20: Groundball through infielder.

Unearned run. But A's win 6-3.

5-6. April 21: Fails to catch line drive and makes a throwing error.

In the second inning, Semien dropped an Albert Pujols line drive with two outs, with a run scoring on the play. Unearned run. His error in the sixth created another unearned run. A's lose 14-1.

7-8. May 9: Groundball through infielder and bad throw.

These came on the same play with two outs in the first inning, with an unearned run scoring as a result. A's lose 7-2.

9. May 10: Groundball through infielder.

Mariners didn't score in the inning.

10. May 11: Bad throw.

Did not lead to a run.

11. May 12: Bad throw.

Did not lead to an unearned run. A's win anyway.

12. May 13: Bad throw.

With two outs in the eighth, Dustin Pedroia reached on an infield single but Semien's error allowed Daniel Nava to score from second. Unearned run. It was the second run in Boston's 2-0 victory.

13-14. May 17: Groundball through infielder and a bad throw.

The first came leading off the fifth and the White Sox would go on to score four runs in the inning, with one unearned. No runs scored from the second error. The White Sox win 7-3 so the four-inning was key, even if only one run was unearned.

15. May 18: Failing to catch the throw from an infielder.

No runs. A's win 2-1.

16. May 20: Bad throw.

No runs scored.

17. May 25: Groundball through infielder.

No runs. A's win 4-0.

18. May 28: Losing the double play on a bad throw.

No runs scored. A's win 5-4.

19. June 3: Groundball through infielder.

No runs scored. A's win 6-1.

20. June 10: Groundball through infielder.

No runs scored. A's win.

21-22. June 14: Groundball through infielder and failing to catch throw from infielder.

The first error with no outs leads to an unearned run. But the A's win the game 8-1.

23. June 28: Bobbled a groundball.

No runs scored in the inning.

24. June 29: Groundball through infielder.

No runs scored. A's win.

25. July 1: Bad throw.

Once again, no runs score in the inning.

26. July 3: Bad throw.

No runs score in the inning.

27. July 7: Bad throw.

No runs scored.

Conclusion

Semien's 27 errors have led to just nine unearned runs. But you can argue the only error that cost the A's a game was the April 11 error that allowed Nelson Cruz to bat with two outs in the eighth inning. Cruz's three-run homer gave the Mariners a 4-2 lead. The A's tied the game before the Mariners won in 11 innings.

Not surprisingly, the A's lead the majors with 81 errors. That means the other 54 errors have led to 33 unearned runs, a more costly ratio than Semien's errors. Semien is drawing a lot of criticism for his miscues, but the truth is that all of those errors have had little direct influence on Oakland's record. That doesn't mean if he keeps booting grounders and throwing balls away that the A's won't eventually pay a bigger price, but don't blame Semien for the A's being 39-48. The errors look bad; they led to one loss. There are other reasons to blame for Oakland's record then Semien's errors.

Update: Semien made his 28th error in Thursday's 6-2 loss to the Yankees. The throwing error came in the eighth inning with two outs, allowing two runs to score, so now his errors have led to 11 unearned runs, although this game was likely decided with the A's down 4-2 without the error.

For more on the A's, check out Beaneball.org.