And Saturday, when Morneau was at the plate in the bottom of the ninth with the Twins trailing, 5-4, with two outs, runners on second and third and facing a future Hall of Famer in Yankees closer Mariano Rivera, it was once again a Mauer bat that Morneau held in his hands.
Whether it was luck or not, the bat worked its magic, as Morneau hit a jammed shot just high enough over second baseman Robinson Cano to score two runs and lead the Twins to a 6-5 comeback victory over the Yankees.
"It's big," Morneau said of being able to get the winning hit off Rivera. "To come back on him, he's one of the best closers in the history of the game, not just right now. He's been in that situation a lot of times, and he's usually the one that wins, so it's nice to see us shaking hands instead of them."
It wasn't quite the way the Twins had drawn up the win after getting off to a 4-0 lead early, but it was certainly sweet, especially for a team that struggled to pick up these type of victories last season.
"We didn't quit after they came back on us," Morneau said. "Last year might have been a little different. We got down on ourselves a lot."
It would have been easy for the Twins to get down after the Yankees scored three runs in the seventh inning to take a one-run lead. But the Twins aren't the same club as they were a year ago, and they found a way to battle right until the end.
One big difference was the veteran leadership provided by second baseman Luis Castillo, who delivered the big hit to start the ninth-inning comeback. Castillo hit a chopper into the infield off Rivera and, using his speed, beat the throw to first. Mauer then came up to the plate and delivered a single to left on a 3-2 hit-and-run, and the catcher advanced a base on the throw to third, putting runners at second and third.
Back-to-back strikeouts by Rondell White and Torii Hunter left Morneau in the spot against Rivera that allowed him to deliver the key hit and become the hero for the day.
So was this a defining moment for the young first baseman and catcher to come up big in such a pressure-packed moment?
"Defining? Sure, it was a great moment for two young hitters," manager Rod Gardenhire said of the contributions made by Morneau and Mauer. "But let's not try to get there too often. When you're there, it's normally not good."
Not many would have predicted the Twins would have even been in that situation with four runs of support over the first few innings and Johan Santana on the mound.
But for the third straight outing, Santana struggled. The southpaw gave up four runs on eight hits over 6 1/3 innings. It wasn't his typical type of performance, but Santana's manager was impressed with the way he was able to get through this one.
"I thought Santana really battled," Gardenhire said. "He didn't have a changeup, not really much of a breaking ball ... he was pretty much all fastballs tonight, and they were jumping on a lot of first pitches. But you know what, he battled his tail off."
Despite not having Santana at his best, the Twins still found a way to eek out a victory over the Yankees. It was the fifth straight win for the Twins and brought them above the .500 mark on the season at 6-5.
All five wins during the streak have been in come-from-behind fashion, something a young Twins squad last season had difficulties accomplishing.
Does this mean that the club is finally growing up?
"I hope so," Michael Cuddyer said. "I'd like to think that we are maturing a little bit and able to get some things done that we couldn't before."
Morneau might agree with that. The first baseman's game-winning hit is the most recent example of his maturation from the player who struggled in key situations for the Twins last season.
Morneau might owe Mauer a little credit, since the change didn't seem to appear until after switching bats. But Mauer might deserve more than just a thanks for his sharing of the bats, as Morneau has done more than a little damage to the catcher's supply.
"I've broken six of them," Morneau said with a smile. "He hasn't broken one yet. But he said as long as I keep getting hits, I can keep using them."
If Morneau keeps delivering game-winning hits like his one on Saturday, it surely won't be a problem.