Michael Chavis of Portland has to leap to catch the throw as Daniel Johnson of Harrisburg steals third base in the third inning Wednesday. (Derek Davis/Portland Press Herald)

PORTLAND — Teddy Stankiewicz continued the trend of strong starting pitching for Portland, but the Sea Dogs could not keep a three-run lead Wednesday afternoon at Hadlock Field and lost to Harrisburg Senators 8-7 in 10 innings.

Ahead 4-1 in the ninth, closer Jordan Weems (2-3) gave up three runs. He came out for the 10th and Harrisburg scored four more for an 8-4 lead.

Luke Tendler’s two-run homer and Jordan Betts’ solo shot closed it to 8-7 with no outs in the bottom of the 10th, but that was all for Portland.

The loss wasted a fine effort by Stankiewicz. He allowed five hits and one unearned run over seven innings.

Michael Chavis and Jantzen Witte both had two RBIs, with Chavis swatting a two-run homer in the fifth.

The Sea Dogs dropped to 42-59, while Harrisburg is 52-50.

Stankiewicz’s performance was in line with recent Sea Dogs efforts. In the past nine games, Portland starters have allowed a total of two earned runs.

Stankiewicz did not issue a walk for the second straight start. He struck out four and lowered his ERA to 4.31. A throwing error led to the unearned run in the third inning.

Portland tied the game in the bottom of the third. Danny Mars singled, reached second on a groundout and scored on Witte’s single.

In the fifth, Mars led off with a single. Senators starter Sterling Sharp delivered a slider to Chavis. It hung and Chavis crushed it over the Maine Monster in left field. Witte doubled in Chavis in the seventh for a 4-1 lead.

Josh Taylor pitched a scoreless eighth, and Weems took the ninth. He was in trouble right away after a walk and double. Weems was on the verge of escaping, after a popup and a strikeout, but Daniel Johnson doubled in two runs, and Carter Kieboom doubled him in, tying the game.

In the top of the 10th — with the mandated runner on second base — Harrisburg recorded three straight hits (two doubles). An error brought in one more run.

In the bottom of the 10th, with a runner on second, Tendler homered to right. Betts followed with a blast to left. With one out, both Jhon Nunez and Deiner Lopez singled. But Jeremy Rivera grounded into a double play.

The Sea Dogs embark on a four-game series in Trenton, starting Thursday. They return to Hadlock Field to host Erie at 7 p.m. Tuesday.

NOTES: The announced paid attendance was a sellout at 7,368 (minus a few absent season-ticket holders) … The Senators were scheduled to next play Bowie in Harrisburg. But FNB Field, which sits on an island in the Susquehanna River, is flooded. The Senators’ games Thursday and Friday have been postponed.

Home plate umpire Derek Thomas watches as Michael Chavis of Portland steps on home plate after hitting a two-run homer to left field in the fifth inning Wednesday. (Derek Davis/Portland Press Herald)Teddy Stankiewicz of Portland delivers a pitch in the second inning Wednesday. (Derek Davis/Portland Press Herald)Deiner Lopez of Portland stretches but can’t reach a ground ball up the middle in the third inning, leading to a Harrisburg run. (Derek Davis/Portland Press Herald)