MIAMI -- Each day of a 162-game season offers lessons to a young team battling through growing pains.
The little things become magnified, and the margin for error is smaller.
On Friday night, it was veteran reliever Chad Qualls who relinquished a one-run lead in the eighth inning, spoiling a solid start by right-hander Tom Koehler, as the Marlins lost, 3-2, to the Rockies at Marlins Park.
After Miami took a 2-1 lead in the seventh on pinch-hitter Greg Dobbs' sacrifice fly, Colorado responded with a pair of runs on three hits.
With one out, Troy Tulowitzki doubled to straightaway center and scored on Michael Cuddyer's single to right. Cuddyer advanced to second on Giancarlo Stanton's throw home, moved to third on Wilin Rosario's groundout to first and scored the game-winning run on Ryan Wheeler's double to center.
As a result, the Marlins dropped to 31-1 when leading after seven innings. Qualls hadn't given up a run since Aug. 8 -- a span of five straight scoreless outings. In his previous 44 games against Colorado, he was 3-0 with a 1.93 ERA.
"[Qualls has] been so good for us, so huge in that eighth inning, [but he] just was up in the zone and flat, and just couldn't close them out and get it to [closer Steve Cishek], " Marlins manager Mike Redmond said. "Too bad. It would've been a nice win tonight in a close game."
Jake Marisnick hit his first career triple to right with one out in the seventh, and Jeff Mathis walked. Dobbs sent right-hander Jhoulys Chacin's 3-2 pitch to right to drive in Marisnick and give the Marlins a 2-1 lead.
Both starters put up zeros until Ed Lucas jumped on the first pitch from Chacin in the fifth for a home run to left-center.
It was Lucas' third homer of the season and first since July 22 against the Rockies at Coors Field. It was just the second dinger by a Marlins third baseman this season. The other was by Placido Polanco -- currently on the seven-day concussion list -- on June 26.
Miami's scoreless innings streak, which dated back to Wednesday, ended at 21. Coincidentally, the Marlins snapped a streak of 37 straight scoreless innings in Colorado last month.
But the Rockies quickly countered with a run in the sixth inning on Friday to even the score.
DJ LeMahieu tripled to center and Tulowitzki walked off Koehler. With runners at the corners and no outs, Cuddyer grounded into an RBI fielder's choice.
"We go out there and we pitch and we do our best to keep the team in the game," said Koehler, who gave up six hits and two walks with five strikeouts. "I already know there's been a couple of games that the offense has bailed me out.
"Situation like today, after we score a run on the big home run by Lucas, I can't go out there and allow the guy who leads off the inning to hit a triple. 'Here you go and come right back in the game.' Shutdown innings are really important, and in that situation I have a chance to put them away and I have to do a better job of doing that."
Koehler, who pitched seven innings, allowed a base hit in each inning except the fourth and worked with a runner in scoring position in four frames.
Miami starters have now surrendered three runs or fewer in 48 of the last 60 games, as well as two runs or fewer in 18 of 25.
In his previous outing against Colorado, on July 22, Koehler limited the Rockies to one run on eight hits in seven innings and struck out seven.
"It's the second time we've seen [Koehler]," Rockies manager Walt Weiss said. "He's got good stuff. He pitched really well against us at Coors Field, and it's tough for a young kid to come into Coors Field and do what he did. From the first inning, I said it's going to be tough to score runs, but we scratched and clawed and found a way to win this one."
Miami didn't collect its first hit off Chacin until Donovan Solano's leadoff single up the middle in the fourth. Despite working a 3-1 count, Stanton struck out swinging and Logan Morrison grounded into a 4-6-3 double play.
With an opportunity to recapture the lead in the sixth, Lucas grounded out to short with the bases loaded. Solano had doubled to center to begin a two-out rally before Chacin walked Stanton and Morrison.
"I had a couple hits today," Solano said. "I just want to win the game. I try to battle every at-bat. We'd like more hits, but it didn't happen in the game."
For Redmond, whose team has now lost four games in a row, the plot is a familiar one.
"It's definitely frustrating," Redmond said. "It seems like Groundhog Day over and over again. Same thing. I know the guys are competing and the effort's there, and I've said that all year and I know it is, but at the same time, too, it's tough sometimes.
"We have to keep grinding. We're a team and we'll work through it together and continue to get guys the swings that they need and hopefully they'll improve -- a lot of guys have. You talk about wins and losses. It gets tough. We've lost a lot of tough games. At the end of it we're going to be better for it."
Christina De Nicola is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.