NEW BRITAIN, Conn. — Inning after inning rolled by and the basepaths were quiet.

The bullpens for the Portland Sea Dogs and New Britain Rock Cats were locked in as the game headed toward the wee hours.

The end finally came, courtesy of Marquez Smith.

Smith blasted a two-run homer with one out in the 15th inning Tuesday night to give the Sea Dogs a 4-2 victory.

Portland (62-66) has won seven of its last eight games and three straight. Portland is 12-6 against New Britain this season, 6-2 on the road, and have won 13 of their last 14 series.

Manager Kevin Boles was waiting to show Smith his appreciation. He took responsibility for sending Smith into an out at the plate in the sixth inning, a run that would have been conclusive in regulation.

“I was praying the whole game because in the sixth inning I killed the momentum,” Boles said. “That was something that can’t happen. It was inexcusable. We’re going to be aggressive, we’ve always been aggressive, but that was a little too aggressive.

“It was a mistake on my part and for Marquez Smith to come up with the homer, I gave him a hug after the game.”

Jeremy Hazelbaker began the 15th with a single to right off Jose Gonzalez (2-2). With Matt Hauser on, Hazelbaker stole second. Smith rocked a 2-0 pitch over the wall in left for his seventh homer. Brock Huntzinger (4-6) pitched three hitless innings to earn the win.

The game lasted 4 hours, 44 minutes.

Much earlier, the Rock Cats reached starter Jeremy Kehrt for a run in the first. Oswaldo Arcia slammed a double that ricocheted off the 16-foot-high center-field wall just inches from the top. Chris Colabello then grounded an RBI single off the glove of diving third baseman Derrik Gibson.

New Britain (68-61) increased the lead to 2-0 in the third. Aaron Hicks and Chris Herrmann singled to put runners on the corners. Travis Shaw then couldn’t come up with a tapper to first by Arcia, allowing Hicks to score.

Meanwhile, Andrew Albers efficiently mowed down the Sea Dogs. After Smith (3 for 6) doubled with one out in the first, Albers set down 14 straight until Gibson led off the sixth with a single and started a rally.

A single by Zach Gentile and Hazelbaker’s one-out double set up a two-run single by Bryce Brentz. Shaw knocked Albers out of the game with a single, but Arcia gunned down Smith at the plate.

“Once we got to a 2-2 ballgame, I wanted to force the action a little bit, but Arcia’s got too good an arm,” Boles said. “He got a great read on the ball but the fact is Marquez Smith bailed me out. I can’t thank him enough.”

Kehrt (5 innings, 2 runs) thwarted a New Britain bid in the fifth. He yielded a single to Hicks and walked two, but the infield turned a 3-6-1 double play. Kehrt is 5-0 in his last eight starts, all Sea Dog wins.

“He’s a guy that can add and subtract on his fastball. He throws a little bit of sink and he throws his off-speed behind in the count,” Boles said. “He limited the damage.”

Caleb Clay tossed three innings of shutout, hitless relief, and Ryan Pressly allowed three hits and struck out three in his three-inning stint for Portland.