Francona, who spent the afternoon hours scrambling because of the right hamstring that has Jason Bay sidelined for a few days, took Youkilis up on the offer.
In addition, reserve outfielder Rocco Baldelli was placed on the disabled list before Thursday's game with a left ankle contusion, thanks to a batting practice mishap in St. Petersburg a day earlier.
Josh Reddick, one day after he was optioned to Triple-A, was summoned right back to the Red Sox to take Baldelli's spot on the roster. Reddick arrived a little more than an hour before the game and might have started in left instead of Youkilis if not for the last-minute travel logistics.
It marked the first time Youkilis started a game in the outfield since 2006, when he started 16 games there.
"We're a little banged up right now and we need somebody to go out and play left field, so I told them I'd go out there and play. I've played right field, too. We're lucky Jacoby [Ellsbury] is healthy, otherwise I'd play center," quipped Youkilis.
Though Youkilis is one of the best corner infielders in the game, he hardly has any training as an outfielder. In other words, his willingness to play there means a lot to his manager.
"So I'm back there talking to Youk and Youk was laughing and said, 'Is this one of those things where I need to play the outfield again?'" said Francona. "It's a way of getting a lot of good bats in the lineup. And he's willing to do it, which amazes me. So I just told him, 'You know what, we'll do it. And I said, 'If you make an error out there, send the [media] to me, because it's my fault.'
"I also think we'll go out and play with a lot of energy and try to figure out a way to win the game. I think you can figure out by the way I'm saying it, it's appreciated what he's doing."
With Youkilis in left, Francona had a chance to give left-handed hitter Casey Kotchman his first start in a Boston uniform at first base. Kotchman was acquired on July 31 for Adam LaRoche.
Youkilis has an outfielder's glove at Fenway, but said he would borrow one from Bay or Baldelli for Thursday's game. Youkilis is expected to play the corner infield for the rest of this four-game series against the Yankees.
"For me, I just go out there and try to get to the ball," said Youkilis. "I haven't played enough to really break it down scientifically, how to play the outfield. I'll just go out there and try to catch the ball and throw the ball and just try to know the situations at hand and do whatever I have to do to try to help this team win."
If the Red Sox are holding a lead in the mid to late innings, or if the game is tied, Youkilis will probably shift back to the infield.
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.