PORTLAND — These are not last spring’s Portland Sea Dogs. They’re barely last month’s Portland Sea Dogs.

Thursday’s doubleheader sweep at the hands of Akron provided more evidence that the Sea Dogs are suffering from the talent drain that inevitably occurs whenever a minor league team piles up wins at a historic clip as Portland did earlier this season.

Akron handed Portland its third and fourth consecutive losses before 7,039 at Hadlock Field, pulling away late in the opener, 4-2, and winning a pitchers duel in Game 2, 1-0.

The sweep meant the Sea Dogs couldn’t make a dent in their magic number to clinch a playoff spot. New Britain’s loss to Bowie Thursday night did, however, reduce it to five.

Binghamton’s win over Erie cut Portland’s lead in the Eastern Division to one game.

The Sea Dogs (75-50) are 9-13 in their last 22 games.

“I’m not sure (what has caused the skid). We’re probably not scoring as many runs as we used to,” first baseman Stefan Welch said. “The pitching’s been doing a great job keeping us in ballgames, but we’re usually a couple hits away.”

The Sea Dogs were at least one hit away from salvaging a split and making a winner of starter Justin Haley, who battled Akron starter Cody Anderson through five scoreless innings.

Keury De  La Cruz’s third hit of the doubleheader put Portland runners at first and third with two out when Welch roped a fastball from Anderson, but right  fielder Anthony Gallas barely moved to record the third out and end the Sea Dogs best and last threat.

“I hit it right on the dot but it was straight at him,” Welch said. “I just thought, ‘Aw, man. What are you gonna do?’ That’s all you can do in that situation. (De La Cruz) had a great at-bat to set him up before.”

Jaime Pedroza broke the scoreless tie leading off the seventh by lifting a hanging slider by Haley into the right field pavilion.

Haley, a 23-year-old right-hander making his second start for Portland since being promoted from High-A Salem on July 30, allowed at least one base runner in each of the first six innings. The first two batters reached in the second, third and fifth frames, but Haley escaped without a giving up a run.

“The moments that he fell out of sync he reigned himself back in and he made some good pitches,” Portland pitching coach Bob Kipper said. “That speaks to his ability to stay in the moment and compete and kind of pitch fearlessly in the face of adversity.”

Haley allowed six hits and five walks while striking out three in 6 1/3 innings.

Anderson (no runs, two hits, four strikeouts, one walk) cruised through his five innings, allowing two-out singles to Michael Almanzar in the first and Kevin Heller in the second before retiring the last 10 he faced. Akron lifted him after just 64 pitches.

Louis Head picked up the win with two innings of scoreless relief.

Game 1 see-sawed through the first five innings.Towering solo home runs by Gallas in the first inning and De La Cruz in the fourth resulted in a 2-2 tie.

The RubberDucks went in front for good in the fifth when Justin Toole’s infield single deep in the hole at shortstop scored Pedroza. They added an insurance run in the sixth on Pedroza’s RBI single.

Luis Diaz  took the loss for Portland, allowing eight hits and four runs,  all earned, while walking three and fanning six in 5 2/3 innings.

“I thought he threw the ball well,” Kipper said. “There were just a handful of guys that really squared him up, one being, obviously, the solo home run in the first inning. But when you look at the contact this afternoon, it was a lot of weak contact. They were able to put the ball where we weren’t.”

“It was just  one of those days,” Kipper added. “Things just didn’t fall together collectively as a club.”

Everything seemed to fall into place for Portland up until mid-July. The collection of highly-touted prospects that made the Sea Dogs the talk of the Eastern League and the Red Sox organization, a team that  was so successful some people wondered if the Double-A roster could swap uniforms with the impotent parent club in Boston, is largely gone.

Mookie Betts, Henry Owens, Blake Swihart and Deven Marrero, the biggest names promoted this summer from the opening day roster, are proof that this has already been a successful season for the Sea Dogs in terms of their primary responsibility, to develop future Major Leaguers.

But, not surprisingly, doing that job so well often results in the team’s win-loss record taking a hit, especially when it’s accompanied by late-season injuries to key contributors such as Sean Coyle and Robby Scott.

Welch is confident the Sea Dogs have just hit a temporary bump in the road and can still live up to the standard they set in April, May and June.

“It’s great seeing guys go up, and the guys that have come up (to Portland) have been doing a great job,” Welch said. “Everyone is meshing really well. Everyone is going for each other. (The turnover) doesn’t affect us that much. We’ve just got to maybe score a couple of more runs and I think we’ll be good.”