OAKLAND -- The .500 mark is proving to be the toughest foe to overcome for the A’s.

For a seventh time this month, the A’s record sits even after Friday’s 9-2 loss to the Mariners at the Coliseum put it at 35-35.

Oakland’s offense established an early 1-0 cushion in the second inning and took the lead again in the third on Matt Olson’s RBI single to right off Mariners starter Marco Gonzales, but the scoring soon became hard to come by. The A’s were held to just two hits after the third and their usual propensity to mash homers was absent. The result was another loss that came on a homerless day -- they’re 1-18 in games in which they fail to hit a home run.

• Box score

“We had a lead briefly and just didn’t play a good all-around game,” A’s manager Bob Melvin said. “It seemed like the first game in a while where we haven’t been at least within shouting distance at the end. They just kept adding on and we couldn’t take advantage of the opportunities we had early on.”

It can be difficult to hit the ball out of the yard when the opposing pitcher is not complying, and Gonzales made life tough on the A’s. The left-hander spent most of the night keeping the ball out of the heart of the zone, inducing early outs, which allowed him to complete seven innings.

“He throws a lot of changeups and cutters,” Melvin said. “He wants to make you expand. He doesn’t want to have to throw the ball over the plate unless he has to. We played into his hands a little bit.”

The long ball would have been useful, but more than one would likely have been required for the A’s after the bullpen allowed the game to get out of hand late.

Starter Chris Bassitt did not have his best command -- walking four batters on the night -- yet managed to keep the A’s within striking distance. His downfall came in the fourth when a Marcus Semien error loaded the bases with no outs. Bassitt proceeded to surrender three runs after the error, but regrouped and pitched into the sixth, allowing four runs (three earned) on five hits and four walks with four strikeouts over 5 2/3 innings.

Semien’s error came on a potential double-play ball, but Bassitt was more frustrated with his walk of Daniel Vogelbach, which he deemed “unacceptable,” to lead off the inning.

“I’m just sick and tired of walking guys,” Bassitt said. “I get guys to 0-2 and don’t put them away. I’m setting myself up to go deep in games and I’m just not doing it. It’s frustrating.”

Issuing free passes has started to become more of an issue for Bassitt. The right-hander has walked 15 batters over his past five starts after walking just five in the previous four. Adding to his frustration on Friday night were two of his walks coming on two-strike counts.

“I guess it’s a little bit of a mechanical issue or thought process,” Bassitt said. “I have to put guys away. One walk is whatever, but four is ridiculous. I need to get that ironed out.”

Wang is human

Melvin went to Wei-Chung Wang in relief of Bassitt with the hope of keeping the deficit at two runs, but that quickly doubled in the seventh when the left-hander served up a cutter over the heart of the plate that was belted by Omar Narvaez for a two-run homer. The two runs allowed snapped what had been an impressive run of 8 1/3 scoreless innings for Wang to begin his A’s career.

“He’s been really good for us,” Melvin said. “Almost a surprise, as well as he’s pitched for us, that he actually gave up a home run.”

Division struggles

The A’s fell to 16-19 in games within their own division, a record they know they need to improve in order to make another run to the playoffs.

“We know the teams that are going to be in it,” Bassitt said. “We’re chasing some good teams and we can’t give games away. I feel like I gave one away tonight.”