Over seven years ago, the Boston Red Sox signed a 17-year-old left-handed pitcher out of Australia for $400,000. Since then, Daniel McGrath has toiled in the minors.

But in 2019, in his second season with the Portland Sea Dogs, McGrath looks to break out.

McGrath, now 25, turned in another dominant performance Thursday night in a 1-0, 10-inning loss to Harrisburg, before 6,280 at Hadlock Field. Tres Barrera won it with a sacrifice fly.

McGrath threw eight shutout innings, allowing two hits and a walk, striking out six.

He hasn’t allowed an earned run with the Sea Dogs in his last 46 innings.

“Doing what I can, coming to the park every day, trying to get better every day,” McGrath said. “Been able to command the fastball and change-up, and working on the curveball.”

McGrath retired the first 10 batters before allowing two singles in the fourth. He then retired 12 straight before yielding his only walk, with two outs in the eighth. He fielded a grounder and threw out the runner to finish his outing (99 pitches/63 strikes).

But McGrath didn’t get a decision because Harrisburg starter Andrew Lee (six innings) and relievers shut down the Sea Dogs

“I like how (McGrath is) changing location, changing eye-level,” Sea Dogs pitching coach Paul Abbott said. “He sells his change-up off his fastball. His command of his secondary pitches is way beyond whatever it has been in the past. That’s his key to success.”

McGrath lowered his ERA to 1.46. More impressively, his ERA in nine starts is 0.55.

“He’s pitching more efficient, more to contact,” Abbott said.

McGrath came up through the Red Sox system as a starter, but stalled in Salem with a couple of injuries. He stayed in advanced Class A for three seasons, the last one in the bullpen.

“Going back there for a third year was kind of a grind,” McGrath said. “I needed a change and moved to the bullpen to kind of spark things. Lowered my arm slot a little bit and been rolling with that the last couple of years.”

Last year, McGrath settled into Double-A, with a 3.63 ERA in 33 appearances (11 starts).

This season he began in the pen but excelled in spot starts and won a place in the rotation.

On Thursday, McGrath showed what he can do, with Ben Crockett, the Red Sox director of player development, in attendance.

“I hadn’t seen a start yet,” Crockett said. “He’s really understanding how to use his stuff. And he’s more confident with throwing his curveball whenever he wants. His change-up has always been a weapon, and his fastball continues to get better and better.”

McGrath made one fill-in start in Triple-A Pawtucket this year, allowing three runs. He could head back to Pawtucket as the Red Sox might want to test him more. McGrath became a free agent last year and re-signed with the Red Sox. He will be a free agent again at the end of this year.

Durbin Feltman relieved and pitched a perfect ninth. Matthew Gorst (1-6) entered in the 10th with the automatic runner stationed at second base – advancing on a groundout, then scoring on Barrera’s fly to right.

In the bottom of the 10th, Jhon Nunez was on second base. He went to third on a groundout, then tried to score on Jarren Duran’s grounder to first but was thrown out. C.J. Chatham grounded to short to end the game.

NOTES: Josh Tobias, just activated, appeared to reinjure his leg in the fourth inning and left the game. … The first 1,000 fans received a Mookie Betts bobblehead. Fan began gathering by 2 p.m., 3½ hours before the gates opened. When they did open, the line stretched to the Portland Expo. The next, and final bobblehead giveaway of the season, will be Aug. 19, featuring Andrew Benintendi.