Dickerson's winning liner, off Sam Dyson (2-1), was almost too hard to end the four-hour, 28-minute game. Marlins right fielder Giancarlo Stanton had time to throw to the plate and nearly erase Nolan Arenado, whose double had opened the inning.
"I knew he [third-base coach Stu Cole] was going to send him," said Dickerson, who grounded out with the bases loaded against Dyson in the Rockies' 13-5 loss Friday night, but waited for the second pitch to win Saturday's game. "Being the 13th inning, it was the right decision, even though Stanton has a great arm. He made a good throw, and luckily Nolan beat it."
The game had seemed to slip through the Rockies' fingertips. The Marlins took a 4-3 lead in the top of the ninth when Adeiny Hechavarria's high, one-hop bounce ticked off the end of pitcher LaTroy Hawkins' glove for an RBI single.
But Dickerson led off the bottom of the inning by sending a 3-1 sinker from Marlins closer Steve Cishek deep into the night for his 19th homer this season. It was the 33rd third-deck homer in Coors Field history, and it handed Cishek his fourth blown save in 35 chances this season.
The one strike of the at-bat came when Dickerson swung off-balance. But when the time came, he kept his legs in good position and did batting practice-type damage.
"I've done it a couple of times in BP," Dickerson said. "We joke around and they tell me, 'Do it in a game.' I got a good pitch and put a good swing on it. It was pretty awesome that it went that far."
The Rockies have won five games in a nine-game homestand that concludes Sunday. It's their first winning homestand since May 1-6. They won 3-of-5 in a May 16-22 homestand, but there is a suspended game with the Giants -- which will conclude Sept. 1 -- hanging in the balance.
"You see the fight we have in these games," said Brandon Barnes, who hit his seventh homer of the season, a two-run shot in the third against Marlins starter Tom Koehler. "What's that? Three come-from-behind wins in this homestand?"
Rockies reliever Matt Belisle (4-6) threw a 1-2-3 13th. The inning ended with a spinning throw by Arenado, whose play was the Rockies' answer to Hechavarria's running over-the-head catch to rob Justin Morneau of a possible game-winning hit in the bottom of the 12th.
"That would have been a tough one to lose after coming close so many times," Rockies manager Walt Weiss said.
Belisle, who fanned one, was one of eight Rockies relievers who combined for 11 strikeouts and no walks. Colorado relievers walked seven in Friday night's loss.
On Saturday, Rex Brothers entered with two out and runners at first and third, then fanned Garrett Jones in a left-on-left confrontation to end the sixth. Juan Nicasio and Boone Logan did their jobs after having pitched Friday, and Adam Ottavino struck out two with one on to end the eighth. Hawkins gave up three hits, all with two out, but struck out two in the ninth.
Nick Masset threw the 10th and 11th, benefiting from a diving play by shortstop Josh Rutledge to start a double play in the 11th. Brooks Brown had a spotless 12th after having thrown two innings Friday. Belisle also pitched Friday.
"We kind of reversed what we did the night before," Masset said. "You could tell everyone was a little angry."
Rockies starter Jordan Lyles came out break-even on a difficult night. Lyles, who pushed across the Rockies' first run when he grounded into a double play with runners at first and third in the third inning, gave up seven hits and three runs, and he struck out five in five innings. He walked five, one with the bases loaded, and hit a batter, but left with the score tied at 3.
The Marlins left 15 on base.
"In one-run games in this ballpark, that's tough," Marlins manager Mike Redmond said. "You can put a big number up quick and in one swing. But we had chances. We had a lot of chances."