MIAMI -- As far as first impressions go, newly acquired reliever Sam Dyson wishes things had begun on a better note.

With Minnesota nursing a three-run lead entering the ninth, Dyson was unable to record an out in his debut in an eventual 5-4 walk-off loss to the Marlins on Thursday afternoon at Marlins Park. Right-hander Cody Stashak surrendered a walk-off homer to Harold Ramirez in the 12th.

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Dyson walked Curtis Granderson before Martin Prado singled, Jon Berti doubled and Brian Anderson walked to load the bases with one run in on 14 pitches.

“Didn't execute, didn't get the job done,” said Dyson, who entered the outing with 1.2 walks per nine innings. “We had the lead. I didn't do my job as part of the team. That's a bad first impression. Hopefully there's no more of those.

“I haven't walked too many guys this year. ... You're never trying to go up there and walk a guy. I'm not trying to walk anybody, that's for sure. I wasn't initially trying to do that, I wasn't trying to work around them. I didn't have it, and that was about it.”

Closer Taylor Rogers, who needed 23 pitches to get through two outings in the first two games of the series, took over and gave up a two-run single to Neil Walker. According to FanGraphs, the Marlins had a 93.3 percent win expectancy after Walker’s knock.

But following a strikeout of Starlin Castro, Rogers intentionally walked Ramirez. He then struck out Jorge Alfaro and Bryan Holaday to escape the jam and send the game to extras.

The Twins have had six players record a save this season, but righty Blake Parker (10, second most) was designated for assignment eight days ago and signed with the Phillies. So manager Rocco Baldelli turned to Dyson rather than initially going with Rogers, who ended up appearing three straight days for the first time since May 26-28.

Righty Sergio Romo, whom Minnesota acquired on Sunday from Miami, had already pitched a scoreless eighth inning.

“Coming from our point of view, the way the game played out, I think it made sense to get him in,” Baldelli said. “It’s a high-leverage, fairly high-leverage situation. It’s a three-run game in the ninth inning. You can question yourself on our end decision-making-wise on what ifs and things like that, but he’s going to pitch in big spots like that for the rest of the year, so I thought it fit well.

“We had Romo up in the seventh, and therefore made it pretty easy to make the decision to bring him in in the eighth because he was already up and hot. So he went out there and did a nice job. We were going to try to stay away from ‘Rog’ if possible, if we could today, so I thought it made sense to get Dyson up. He was ready to go. He’s been off for a few days, and get him in there and he’s, like I said, he’s going to be a guy that we lean on and days like today, they’re going to happen.”

With the defeat, Minnesota (66-42) missed out on moving a season-high 26 games over .500 and recording its eighth sweep of the year -- first since late May.

After finishing their trip 5-2, the Twins head back to Minnesota for a crucial 10-game homestand with matchups against the 40-win Royals, the National League East-leading Braves and the Tribe, who sit on the heels of the Twins in the American League Central.

Dyson wouldn’t use the fact that he arrived around the bottom of the third inning after taking a flight from Philadelphia on limited sleep as an excuse. The right-hander will have plenty of time to make up for it during the stretch run.

Between Dyson and Romo, the pair entered the series finale with a 2.94 ERA, 19 saves (in 21 opportunities), 18 holds and a 1.03 WHIP in 2019. Both have postseason experience, and they help fortify the backend of the bullpen.

“It's a great feeling,” Dyson said of joining the postseason hopeful Twins. “Obviously they're in first place for a reason. They've got a lot of pieces here that have done well all year. ... You don't want to screw the momentum up, you want to help out and do your part, and look forward to tomorrow.”