SAN FRANCISCO (CBS Sports) — Plenty of us look at our paycheck every week and hope some kind of mistake puts a few extra bucks in our pockets. San Francisco Giants left-hander Jeremy Affeldt benefited from such a mistake in 2010, a mistake that put an extra $500,000 in his pocket.

Affeldt, 33, discussed the mistake in his newly released book, To Stir A Movement. He ultimately decided he couldn’t keep the extra money and sleep well at night. It was one or the other, so the money was returned. They reworked his contract to remove the extra $500,000.

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He owns a 3.24 ERA in 8 1/3 innings this year while missing time with an oblique strain. He originally signed with the Giants before the 2009 season and has pitched to a 2.75 ERA in the five years since. Affeldt was a key bullpen cog in the team’s 2010 and 2012 World Series wins.

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READ MORE from CBS Sports on Affeldt’s payback to the Giants.

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