ST PETERSBURG -- A good barometer. That was the phrase used by new Orioles manager Buck Showalter in describing what this three-game set in St. Petersburg, against a Rays team in the thick of a pennant race, would mean for his last-place club.

Following the Orioles' resounding 5-0 series-opening win, the measuring isn't getting any easier simply because Showalter's O's are reaching new heights. Friday's victory -- in front of a crowd of 24,277 at Tropicana Field -- improved Baltimore to 9-2 under Showalter, marking its best 11-game stretch since April 24-May 7, 2005.

"I know what the games mean to them," Showalter said of the Rays, who are two games behind the American League East-leading Yankees. "But I also know what they mean to us in the future and where we're trying to head. I've been in their shoes, where this time of year, every game is of such importance. It's important to us, too. It's not like we're just letting it fly with reckless abandon. We're playing good baseball and it's showing up on the scoreboard."

And a season once thought to be marked by a new standard in losses and futility finally appears to be back on track. Since Showalter took over on Aug. 3, the O's starters have pitched to a 2.62 ERA and the offense has hit .382 (34-for-89) with runners in scoring position, plating 54 runs and posting a .304 team batting average.

"It's not a coincidence that we've turned it around since Buck showed up," said starter Jeremy Guthrie, who tossed six scoreless innings and continues to establish himself, as Angels manager Mike Scioscia recently attested, as one of the AL's premier right-handed pitchers.

"We know what he expects and we've played good baseball with him here. No magic formula, but maybe just a good shift in gears for us."

The evidence is everywhere: from Nick Markakis' over-the-fence grab in foul territory to retire Evan Longoria, to Matt Wieters' 10-pitch walk to chase Rays starter James Shields from the game. These Orioles are moving runners, collecting two-out hits, and in the case of reliever Michael Gonzalez, exorcising old demons.

"We're doing things the right way," said infielder Ty Wigginton, who made a pair of diving stops at first base.

"The attitude along the whole team has gotten better. If something does go wrong, it's not that big of a deal. Nobody's really worrying about it. The next guy's going to pick him up."

It started, just as Showalter's inaugural game did, with a quality start from Guthrie. Emerging as the clear ace of the staff, Guthrie lowered his post-All-Star break ERA to 1.51 in his sixth second-half outing and team-high sixth straight quality outing. On Friday, he held the Rays to just two hits and picked up his fourth win in five starts in the process.

"[This] is the best I've ever seen him throw the ball," Wigginton said. "It's impressive to watch. It's a lot of fun to play behind."

It was even more impressive given that Guthrie didn't have his best stuff, admitting it was a battle to hold the Rays in check.

"Hopefully, in those circumstances, you can do the best that you can to limit the damage when you don't feel up to your best," he said. "That's what I had to fight to do."

By any measure, he succeeded, retiring 12 of 13 batters after Carl Crawford's first-inning single. Crawford's blooper was the Rays' only hit through the first five innings, as Guthrie battled through location woes to record his first career win in seven starts inside the Rays' home dome.

The Rays wouldn't get their second hit until two outs into the sixth, when Felix Pie lost Matt Joyce's routine fly ball in the white catwalks, turned the wrong way and fell down. Guthrie got Willy Aybar to fly out to keep his shutout intact.

"If you make a mistake, you make a mistake," said Pie, who tied a season high three hits to more than make up for his defensive miscue. "Everybody's having fun now. Everybody is smiling."

The O's offense, which entered the game averaging nearly five runs per contest under Showalter, jumped on the struggling Shields. Shields, fresh off allowing eight runs over four innings in his last outing against Toronto, yielded a three-run first. Wigginton and Luke Scott, who later homered, hit a pair of two-out singles and Adam Jones drove both of them in with a triple to right field. Jones scored on Pie's double -- the O's fourth consecutive two-out hit -- to work Shields for a 34-pitch first inning.

"They're underrated," said Shields, who surrendered another run in the fourth but was backed by a defense that turned a pair of inning-ending double plays to help extend his outing. "I believe that they're a good team. I just don't think that they put it together at the beginning of the season like they should have."

The signs are there now, as Friday's win puts the Orioles at 3-1 on the six-game road trip and guarantees them at least a .500 showing. They aren't there yet, but the young and largely inexperienced O's are starting to learn how to win.

"That's always a process," Showalter said. "We lost yesterday, and it was good to see us come back and get back on the right foot. The road is a tough place to play. ... The resiliency and the challenge emotionally of a Major League season is what separates a lot of teams."