SEATTLE -- Seattle starter Hisashi Iwakuma came within one out of his first complete-game shutout on Saturday night, but a two-run homer off the bat of Oakland's Brandon Moss wasn't enough to dampen the Mariners' night.

Seattle's 6-2 win over the division-leading A's made things a little more interesting in the American League West. The Mariners pulled to within seven games of Oakland, and the second-place Los Angeles Angels are now just one game back.

"This is a team you want to beat," said Mariners second baseman Robinson Cano, whose two-out, three-run homer in the eighth inning gave Seattle a 6-0 lead. "They're in first place, so this is the team you want to catch."

The Mariners still have a long road to hoe after the All-Star break, but they're doing their best to make the AL West interesting. Seattle (51-43) has now beaten Oakland (58-36) on back-to-back nights heading into Sunday's series finale.

"They're ahead of us, so to catch them we've got to go through them," said third baseman Kyle Seager, who gave Seattle a 3-0 lead with a two-run homer in the fifth inning. "This is definitely a team you have to beat to get where you want to go."

Iwakuma (8-4) extended his scoreless innings streak to 20 innings before Moss tagged a two-out, two-run homer in the top of the ninth inning. Reliever Yoervis Medina came on and finished off the win with just one pitch.

Iwakuma allowed five hits and no walks on 104 pitches in 8 2/3 innings. The last time Iwakuma had allowed a run before the Moss homer was in the first inning of a July 1 start at Houston.

"It would have been the perfect scenario," Iwakuma said of getting the complete-game shutout, "but you've got to tip your cap. I threw a fastball away and (Moss) got a hold of it."

The A's have now lost four of five and are in danger of going into the All-Star break deadlocked with Los Angeles atop the AL West standings.

"It has been a fight to score a bunch of runs," said A's manager Bob Melvin, who has been missing two-thirds of his starting outfield because of injury this series. "On top of that, we have had two well-pitched games against us."

Seager, just days from making his All-Star debut, hit a two-run homer to put Seattle ahead 3-0 in the fifth inning and Cano continued his torrid hitting pace with a three-run shot in the eighth.

Cano went 3-for-4 and is 13-for-24 on the current homestand; he has multiple hits in each of Seattle's past four games. Cano had singles on two of his first three at-bats.

"He hasn't really gotten hot yet," Mariners manager Lloyd McClendon said. "As the weather's starting to heat up, I think you'll see him heat up. You're starting to see the real Robbie Cano."

Oakland starter Jesse Chavez (7-6) allowed three earned runs and 10 hits in 5 2/3 innings. He gave up the home run to Seager in the fifth inning. Reliever Jim Johnson served up the Cano shot with two outs in the eighth.

"He battled tonight," Melvin said. "He gave up some hits, but really just the Seager home run was the big blow."

The Moss home run in the ninth ended an Oakland streak of 16 scoreless innings.

Two unlikely hitters put the Mariners ahead 1-0 in the second inning. Left fielder Dustin Ackley drove in his first run since July 1 with a one-out single, which brought home Corey Hart from second base after Seattle's struggling designated hitter doubled in front of Ackley.

Chavez ended up walking two hitters to load the bases in the second, but he got out of the jam by way of a James Jones groundout. Seattle stranded seven runners in the first four innings.

Iwakuma struck out the side on 15 pitches in the first inning and had a four-hit shutout going before Moss took him deep in the ninth.

Mariners shortstop Brad Miller was ejected from the game in the bottom of the fourth inning. After getting called out on strikes, Miller said something over his shoulder to home plate umpire Bob Davidson, who promptly tossed him.

NOTES: Before Saturday's game, the A's placed 1B Alberto Callaspo (hamstring) on the 15-day disabled list and recalled INF Andy Parrino from Triple-A Sacramento. Callaspo, who is hitting .234 with three home runs and 31 RBIs in 83 games this season, strained his right hamstring while running out a ground ball in Friday's loss to Seattle. ... Mariners closer Fernando Rodney was added to the All-Star roster on Saturday, replacing Tampa Bay RHP David Price. Rodney is the fourth Mariners player to be named to the American League roster, marking the highest total by the team since Seattle sent five players to the 2003 All-Star Game. Rodney was leading the AL with 27 saves heading into Saturday's game against Oakland. ... Mariners LHP James Paxton, who was expected to be a part of the rotation this season but has not pitched since early April because of a strained lat muscle, could make his first rehab start during the All-Star break. Paxton threw a 53-pitch simulated game on Saturday afternoon and the Mariners will decide Sunday what his next step will be. ... Oakland CF Coco Crisp (neck) was out of the lineup for the third day in a row Saturday night. ... Mariners C Jesus Sucre got his first start of the season Saturday, when starter Mike Zunino was getting a routine day off. Sucre was called up from Triple-A earlier in the week, replacing veteran John Buck as Zunino's backup.

NOTES: Before Saturday's game, the A's placed 1B Alberto Callaspo (hamstring) on the 15-day disabled list and recalled INF Andy Parrino from Triple-A Sacramento. Callaspo, who is hitting .234 with three home runs and 31 RBIs in 83 games this season, strained his right hamstring while running out a ground ball in Friday's loss to Seattle. ... Mariners closer Fernando Rodney was added to the All-Star roster on Saturday, replacing Tampa Bay RHP David Price. Rodney is the fourth Mariners player to be named to the American League roster, marking the highest total by the team since Seattle sent five players to the 2003 All-Star Game. Rodney was leading the AL with 27 saves heading into Saturday's game against Oakland. ... Mariners LHP James Paxton, who was expected to be a part of the rotation this season but has not pitched since early April because of a strained lat muscle, could make his first rehab start during the All-Star break. Paxton threw a 53-pitch simulated game on Saturday afternoon and the Mariners will decide Sunday what his next step will be. ... Oakland CF Coco Crisp (neck) was out of the lineup for the third day in a row Saturday night. ... Mariners C Jesus Sucre got his first start of the season Saturday, when starter Mike Zunino was getting a routine day off. Sucre was called up from Triple-A earlier in the week, replacing veteran John Buck as Zunino's backup.