He saved the Dodgers' 6-5 win over the Rockies, their three-game win streak and their depleted bullpen. He did it by qualifying for a save every which way you can.
According to Major League rules, there are three ways to qualify for a save: 1) enter the game with a lead of three or fewer runs and pitch at least one inning; 2) enter the game with the potential tying run on base, at bat, or on deck; 3) pitch three or more innings with a lead and finish the game.
You only need to meet one of the three criteria. Troncoso met all three.
With Jonathan Broxton, Ronald Belisario and Hong-Chih Kuo spent from the night before, manager Joe Torre was asked before the game who would be his closer, and he said it would be the last pitcher that pitched.
Nobody -- not even Torre -- thought that would be Troncoso when he brought him in, leading by a run, after five shaky innings from rookie starter James McDonald, who wound up with his first Major League victory.
But Troncoso kept mowing down the Rockies with a power sinker and Torre kept sending him out there inning after inning until there were no more innings needed. Troncoso pitched four of them about as well as you can in Coors Field, protecting that one-run lead by allowing only an infield single and no walks. He not only defeated Colorado but its intimidating ballpark, where middle reliever ERAs usually get multiplied.
"That was incredible," said Torre, who changed his mind about hitting for Troncoso after he went 1-2-3 his first inning.
Troncoso said when he was sent up to bat in the seventh, he realized he might be pitching for a while.
"After that, with his pitch count and getting left-handed hitters to hit ground balls, that was huge," Torre said. "That's as good a job as anybody could do, in this park, against that club. We knew coming in [because of his tired bullpen], we had to score a lot of runs or get something of a surprise, and that was at the top of the list."
Troncoso had pitched only one other time in Coors Field, last July 22, allowing four runs on six hits in one inning that sent his rookie ERA to 6.11. That's what Coors Field usually does to middle relievers. But Troncoso's ERA is down to 1.54, a dramatic turnaround from the 6.57 spring ERA that would have had Troncoso starting the season at Triple-A except that, according to Torre, "nobody else was knocking the door down."
"Last year, we saw he was durable, he could get the ground ball, but we didn't see it consistently all spring," he said. "The last time [1 2/3 scoreless innings in Houston on Tuesday night] was what we saw last year. And after the game tonight, I told him he never has to prove himself again. That's a tough spot, a one-run lead, and he didn't give them anything. Pretty amazing."
Pitching coach Rick Honeycutt said Troncoso ironed out some mechanics with extra bullpen work in the mornings as Spring Training neared its end. He also said Troncoso's improvement accelerated when he gained confidence in supplementing his sinker with an occasional breaking pitch.
When Torre had his great Yankees teams, he had a Ramiro Mendoza who could do what Troncoso did Saturday night. It was needed because McDonald experienced a replay of the Arizona meltdown two weeks ago, right down to the walk of the opposing pitcher.
With Russell Martin (four RBIs) keying a four-run first inning with a two-run single, the Dodgers' offense had given McDonald a 4-0 lead in the first inning, but he gave back three runs in the third, with three walks. The offense tacked on two more runs in the fourth with Martin's second hit, but McDonald issued a two-out walk in the fifth to Todd Helton, and Garrett Atkins followed with a two-run homer.
"Walks -- they kill you," McDonald said. "My hat's off to Troncoso, a great performance. I feel like I'm getting myself in jams more than the other team is getting me. After a walk, I need to step off and slow things down. Instead, I start speeding things up."
Torre said he expects McDonald to make his next start Thursday, although Jeff Weaver made his first Triple-A start Saturday and, with Hiroki Kuroda out indefinitely, McDonald likely will need to make some quick improvements to retain his current role.
"He'll throw a couple great innings, then all of a sudden, one inning jumps up. It's a learning experience," Honeycutt said. "You like that he keeps battling, but you don't like that he seems to lose his cool for two or three hitters at a time."
Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.