With a runner on second and none out, Giambi leaped to snare a hot line drive off the bat of the Blue Jays' Marco Scutaro, likely saving a run in New York's 3-2 eventual victory.
Giambi has spent the last few seasons logging more at-bats as a designated hitter, but with his renewed focus on health and mobility, the Yankees believe that he can be a contributor defensively. So far the plan is to give him every chance to prove it.
"I love to be on the field," Giambi said on Wednesday. "That's why I've never been a fan of the DH. You're a part of the game and a part of the team."
The 37-year-old Giambi, playing the final year of his contract, has convinced manager Joe Girardi that he will hold up to the rigors of everyday duty in the field.
The Yankees have no shortage of capable defensive options at first base, carrying not only Shelley Duncan and Morgan Ensberg but infield jack-of-all-trades Wilson Betemit. Yet in the late innings of Tuesday's close game, Girardi opted to stay with Giambi and allowed him to play all nine innings.
Giambi reported to camp several pounds lighter and with greater mobility after surgery corrected his injured left foot last season, and Girardi targets that -- as well as curiosity -- as the factor in his increasing trust in Giambi.
"That's why we left him out there -- because we saw it in Spring Training," Girardi said. "I want to watch him and see how he is physically."
After missing two months last season with a torn left plantar fascia, Giambi feels primed for a rebound campaign. Having discovered orthotic inserts to guard against future foot injuries, Giambi did all of his running on flat ground this winter and said that he feels more agile.
Girardi also suffered from plantar fasciitis toward the tail end of his career in the big leagues, so he can sympathize with what Giambi went through last year, when he hit .236 with 14 homers and 39 RBIs in 83 games.
"I put it all aside," Girardi said. "That foot injury he had, I have that in both [feet]. Now that I don't play anymore, it's much better, but it's miserable. You find that you change the way that you walk, and you change the way you run. I think it adds to being injury-prone, but now it's fixed."
The numbers seem to indicate that the Yankees may be better off if Giambi is able to stay on the field, allowing Hideki Matsui to remain as the everyday designated hitter. A lifetime .309 hitter with a 1.008 OPS as a first baseman, Giambi has hit just .243 as a DH, with a .861 OPS. The trend didn't hold true last year, when Giambi hit .184 as a first baseman, but he was limited to 46 at-bats there.
"It's fine. I did it every day with the A's," Giambi said. "'Venticinco' is back."
Bryan Hoch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.