The veteran set a Major League record with 1,701 chances without a miscue at first base. His last error at that position was on July 4, 2006, also against Tampa Bay. Youkilis converted eight chances on Friday night and another 10 in Saturday's loss to reach the mark.
Youkilis broke the previous record, set by Stuffy McInnis over the course of 163 games from 1921-22.
"I didn't even know when I did it. I go out there, play the game and it's not a big deal to me," Youkilis said. "Winning ballgames right now is probably my main [concern]. We need to get this team back on track."
Youkilis isn't trying to be humble, he actually wasn't even aware of how close he was to making history. After tying McInnis' mark, Youkilis tossed the ball to a fan, as he usually does when he ends an inning.
Manager Terry Francona was equally focused on the game.
"I knew he was approaching it, and the only reason I did know [was] because [traveling secretary] Jack McCormick came running down. MLB wanted the ball," Francona said. "That's the only reason I knew it. In a 1-0 game [at the time], [I was] not really paying attention, but I was aware of it."
The record-setting play was a groundout by Eric Hinske, fielded by second baseman Dustin Pedroia, who safely tossed it to Youkilis in the seventh inning.
"I haven't really known until people have told me," Youkilis said. "Hopefully, that's the end now. I'll keep throwing balls up in the stands."
Brittany Ghiroli is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.