Luis Martinez’s batting average is rising with the temperatures.

The veteran catcher rapped a season-high three hits Wednesday for the Portland Sea Dogs, who nonetheless dropped a fourth consecutive game, 8-3 to the Binghamton Mets before an announced crowd of 3,114 at Hadlock Field.

Martinez, 30, finished the homestand on a high note, raising his average from .182 to .229 after collecting two singles and a double.

“I was just more relaxed, trying to get a pitch I can handle and put a good swing on it,” Martinez said. “I think the cold had a lot to do with (an early season slump). I’m not used to it.”

Martinez, a native of Miami, split time between Triple-A Salt Lake City and Sacramento last season, batting .246 with five home runs. He has also appeared in the major leagues with San Diego and Texas. The journeyman was signed by Boston to give a veteran presence to the Portland pitching staff, which entered Wednesday’s game with a 5.42 ERA.

“Having seen pitchers pitch at the highest level, I think he can provide some really good insight to these guys,” Portland Manager Billy McMillon said.

On Wednesday, Martinez watched as Portland starter Mike McCarthy struggled to keep the ball down in the zone. McCarthy, who entered play with 11 consecutive scoreless innings, was tagged for six runs in four innings and fell to 2-2. He surrendered a pair of home runs, the second of which effectively ended the evening for McMillon and him.

Binghamton second baseman Jairo Perez drilled a pitch 419 feet down the left-field line. Plate umpire Blake Felix ruled it a foul ball. But after the Mets protested, Felix consulted Eric Gillam, who was stationed at second base on the play. The call was overturned, giving Binghamton (12-8) a 6-2 lead and bringing McMillon out of the dugout.

The umpires appeared to have reached the proper conclusion, but that wasn’t what angered McMillon, who eventually was ejected.

“I’ll go to my grave not understanding how the guys in the middle of the diamond can see if a ball is fair or foul down the line,” McMillon said. “I believe if (Felix) can see that, then that ought to be his call all the time.”

Martinez, who had the same vantage point as Felix, said the ball tailed and appeared to go foul. But he acknowledged it was difficult to tell from home plate.

Martinez doubled in a run in the bottom of the fourth to cut the deficit to 6-3. And then he helped relief pitcher Kyle Kraus get through four decent innings in his second stint with Portland. Kraus gave up five runs in three innings in his first appearance as a Sea Dog. On Wednesday, he returned from Class A Salem and worked quickly, his lone blemish a two-run homer by Aderlin Rodriguez.

Portland (7-13) has been outhomered 17-5 on the season.

“His two-seam (fastball) was working very well,” Martinez said. “He needs to keep it going. Besides that one pitch, everything else was awesome.

“I’m trying to get to know the personalities and the pitching staff. I try to help them out the best I can with all my knowledge. I never get tired of playing.”