Bay missed the first three games of the series with right hamstring woes, and his absence was felt with Boston being shut down for 24 consecutive innings.
"A lot of people have made a big deal that it's this series or whatever it is," said Bay. "Regardless of who we're playing against, I want to get out there as fast as I can. Obviously, the offense has struggled a little bit, but we've also faced some really good pitching. It's another reason to get out there, not that you need it. I'm still going on how I feel. Today was the day I picked."
In the past couple of days, Bay's hamstring felt noticeably better.
"Yeah, actually a lot better," said Bay. "I really don't feel anything back there. I was still a little sore in [St. Petersburg], but soreness and pain are two different things. Knock on wood, I feel back to normal, so to speak. I still have to go back out there and play."
As for Ortiz, he had just four hits in 32 at-bats in the first eight games of the road trip. The designated hitter had been dealing with the revelation that he tested positive for performance-enhancing drugs in 2003.
"We have four righties coming up against Detroit and we're going to get in late," said Francona. "I think he's exhausted mentally and physically. I think it makes sense tonight. We can use [Mike] Lowell's bat [at designated hitter], we can get Victor [Martinez] at first and David's sitting there late in the game if we need him."
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.