OAKLAND -- Even as the Mariners have racked up victories and catapulted themselves into the playoff hunt, detractors have constantly pointed to one stat in an attempt to undermine the team’s legitimacy: run differential.

Yes, Seattle’s run differential woes are true. At the end of Tuesday afternoon’s 5-1 win over the A’s at Oakland Coliseum, the Mariners’ run differential is minus-56. Every other team in the league with a run differential in that range has a sub-.500 record. But Seattle (69-58) is winning, and the team couldn’t care less what story that pesky number might be attempting to tell.

“Somebody just told me our run differential was minus-9 this trip, but our fun differential was about plus-90,” said manager Scott Servais. “We’re going with that, and we’re going to ride that one a little bit.”

The Mariners’ run differential during their eight-game road trip against the Rangers, Astros and A’s was, indeed, minus-9. What ultimately matters, however, are wins and losses, and the club will head back to Seattle having won six of its past eight games away from home.

Given how most of Seattle’s wins have come as of late, it was almost odd to enjoy a relatively stress-free four-run win, one that was highlighted by another strong performance by Chris Flexen. The right-hander, who has posted a 2.59 ERA in August, allowed just one run across 6 2/3 innings with five strikeouts to one walk, penning another chapter in what has been a stellar year.

“To see how [Flexen] has grown and how he’s developed -- the confidence, the stuff, everything -- has just been awesome to see,” Servais said. “We’ve been riding him. [He's been] one of our most consistent guys all year long.”

Flexen’s afternoon got off to a rocky start, as he allowed three straight singles in the first inning to Starling Marte, Matt Olson and Mitch Moreland, the last of which produced a run. From there, however, Flexen pretty much cruised until the seventh inning, when fatigue started to creep in.

Flexen retired the first two batters in the seventh inning, but one of those outs came by way of an 11-pitch battle against Sean Murphy that ate into his pitch count. After retiring Murphy, Flexen allowed a double to Elvis Andrus and walked Mark Canha, putting runners on first and second with two outs.

With Flexen’s pitch count already having crossed the century mark, he was pulled from the game, falling just short of completing seven innings in back-to-back outings. He covered his mouth with his glove as he walked back to the dugout, likely displeased that he was unable to get through the frame.

While Flexen couldn’t finish the inning, Drew Steckenrider was right there to shut the door on Oakland’s two-out rally. Steckenrider only needed one pitch to retire Marte, getting the outfielder to fly out, and end the threat and secure Flexen’s latest start. After Steckenrider held firm, the Mariners put up two more runs in the next half-inning, giving Seattle some breathing room.

With a four-run cushion heading into the bottom of the eighth inning, Servais ended up staying with Steckenrider, who held the A’s scoreless across 2 1/3 innings and recorded his sixth save in what was the longest outing of his career.

Aside from the jam in the seventh inning, the win -- Seattle’s third straight -- was relatively stress-free. The same can’t be said about the Mariners’ dramatic victories on Sunday and Monday against the Astros and A’s, respectively.

In both contests, Seattle entered the ninth inning down a run. And in both contests, Ty France tied the game up with a shocking solo home run, setting the stage for a pair of stunning victories.

Regardless of how the games have unfolded, the Mariners have done a whole lot of winning recently. Seattle has now won 10 of its past 13 games, and Oakland has lost nine of its past 12, so the Mariners sit one game behind the A’s, who are 2 games back of the second American League Wild Card spot.

If the Mariners can continue their winning ways, despite what the peripheral numbers say, there’s a chance they could find themselves occupying that second Wild Card spot in the not-too-distant future. And should they usurp the Red Sox and A’s, this team will have a heck of a time doing it.

“It’s the most enjoyable team I’ve ever been on,” said catcher Tom Murphy, who had two hits and drew a walk in the win. “To be winning with this team, it’s truly special, and it’s something we expected of ourselves.”