Pedro Florimon's two-run double highlighted a three-run sixth inning and rallied the Twins to an 8-7 win over the Marlins at Roger Dean Stadium.
From 2005-09, Redmond was a backup for Gardenhire.
Until the sixth inning, Redmond was in position to get the best of his former skipper.
But the Twins came back from two runs down and took a 6-5 lead in the sixth inning off Steve Cishek. Two of the three runs were unearned. Drew Butera delivered an RBI single and Florimon came through with the decisive two-run double.
There was plenty of offense early, with each team scoring in each of their first two innings.
Minnesota grabbed the lead in the first inning on Jeff Clement's RBI single off Henderson Alvarez.
Miami countered with three runs in the first inning off Vance Worley, who gave up four runs (three earned) in two innings.
"He said it was just one of those days where he felt he couldn't get a ball by anybody," said Gardenhire of Worley. "It seemed like a good pitch to him and they put it in play. It looked like a ball they should swing and miss and they'd put it in play. Just one of those days."
Giancarlo Stanton lifted a sacrifice fly to center, scoring Juan Pierre. Donovan Solano and Chris Coghlan each added RBI singles.
In the second inning, the Twins tied it at 3 on Aaron Hicks' sacrifice fly and Jamey Carroll's run-scoring single.
Miami reclaimed a 4-3 lead in the second on Kyle Skipworth's double and Pierre's run-scoring single.
Adeiny Hechavarria's infield RBI single in the third padded the lead to 5-3.
Kevin Kouzmanoff made the final margin closer with a two-run homer in the ninth inning.
"Our pitchers were up in the zone for most of the day," Redmond said. "We just didn't execute a whole lot of pitches out there in a couple of those innings. It seemed like when we missed, we missed up in the zone. The Twins, they're scrappy. They put balls in play and make things happen. That's what they did today."
Up next: Right-hander Kyle Gibson starts his second game of the spring for the Twins. He pitched two scoreless one-hit innings last Sunday against the Rays. Boston counters with right-hander Clay Buchholz for the 1:05 p.m. ET contest at Hammond Stadium. It will be Joe Mauer's final start before departing for the World Baseball Classic.