Rosario wasn't alone in letting this game -- a deflating 5-3 loss to the Marlins at Coors Field in front of 33,165 -- escape.
Ottavino had two quick outs before giving up two singles to put runners at the corners. Wilton Lopez, a day after forcing a key groundout in a win, gave up four ninth-inning runs, and the Rockies' offense didn't manage a run until a futile bottom-of-the-ninth comeback try.
The Rockies came out of the All-Star break and into a 10-game homestand hoping to make their move in the National League West. But, having faced the Cubs and the Marlins, the Rockies are 3-4 and must sweep the Brewers to finish above break-even on the stand. They dropped three of four to the Marlins, who are last in the NL East.
"I've got to block that ball," said Rosario, who has struggled to keep balls in front of him in key situations this season. "That's my responsibility. I need to put myself down in front of the ball. It didn't happen on that pitch.
"We paid. Maybe if that run doesn't score, maybe we come back the next inning and win it."
What's wrong with the Rockies?
These days, it's almost everything but starting pitching. Most perplexing is an offense that managed just seven runs in the series. Yes, the Marlins displayed bright young starting pitching. On Thursday, Nathan Eovaldi held the Rockies to three hits in six innings before the delay and nearly matched Nicasio. Winning pitcher Dan Jennings threw a scoreless seventh, and after Kevin Slowey struggled, Steve Cishek earned his 20th save. Cishek ended the game by forcing Jonathan Herrera into a double-play grounder.
And if the day wasn't bad enough, Carlos Gonzalez, who entered the game tied with the Pirates' Pedro Alvarez for the NL home run lead with 26, left the game in the fourth inning with an aggravated right middle finger sprain. Gonzalez originally suffered the injury before the All-Star break in Arizona and has played in pain since. It worsened after he struck out against Eovaldi in the first inning Thursday.
Now the Rockies are trying to keep the season from deteriorating.
An NL West in which no one has taken charge has kept them relevant, but since a strong start, the Rockies haven't succeeded at a pace of a bona fide contender. Colorado began 13-4 and Miami was 4-13. Since then, the Rockies, who had three hitters start the All-Star Game, are 36-50, and the Marlins, who are fully into a youth movement, are 34-49.
Especially scary for the Rockies is they have three straight three-city road trips on the horizon.
"We've got to play better," Rockies manager Walt Weiss said. "There's no way around it. We've got to get to the point where we put together a run.
"We saw some good, young arms, no question, but at the same time, they caught us at a time where our offense has stalled a little bit. That's pretty obvious. We've got to be better than that."
The Marlins were better than they've been at any point this season.
"It was phenomenal," Marlins manager Mike Redmond. "If you had told me coming in here that the highest-scoring game would be five runs, I would have told you, you were crazy, all the games that I've played here over the past 13, 14 years.
"I give our guys credit, our starters did a great job, got deep into games, that bullpen just continues to put up zeroes and keep us in ballgames."
With the exception of Drew Pomeranz's poor start in Monday's series opener, the Rockies could say the same about their starting pitching. Nicasio's nine strikeouts were one shy of his career high, and he has given up one run and eight hits in 19 innings over his last three starts.
"I was not looking for the strikeout. I tried to throw more strikes, locate the fastball and try to go deep in the game," Nicasio said.
Late-innings stalwart Matt Belisle had appeared in three of the Rockies' previous four games and was not available. Ottavino began the eighth by striking out Donovan Solano and Jake Marisnick, before Rob Brantly and pinch-hitter Greg Dobbs singled into a deep-playing outfield to put runners at first and third. Ottavino missed low and far outside the zone with a 1-1 slider, and Rosario's backhand attempt came up empty, so Solano scored.
"That's how quick an inning can happen," Ottavino said. "I thought I threw the ball all right, and nothing went my way."
Lopez gave up doubles to Christian Yelich and Giancarlo Stanton, and Solano's second homer of the season for a crushing 5-0 deficit.
"It looked like he was really on his way to ironing some things out," Weiss said. "He's a great competitor, no question about it."
Michael Cuddyer's RBI double in the ninth off Slowey averted a shutout. Rosario added an RBI single off Slowey, and was in scoring position with no outs.
Cishek worked Charlie Blackmon into a popup. Rosario scored when Stanton misplayed Nolan Arenado's single in right field, but Cishek forced Herrera into a double-play grounder.