ST. PETERSBURG -- The experiment of putting Pedro Ciriaco in center field didn't last long Thursday night.

Making just his second career outfield start, Ciriaco was pulled in the middle of the fourth inning during the Red Sox's 7-4 loss to the Rays after allowing two catchable balls reach the ground.

In the bottom of the second, both he and right fielder Daniel Nava were going for a ball in right-center, but it landed between the pair, resulting in a double for Evan Longoria. The following inning, B.J. Upton hit a high-flying ball almost right to Ciriaco, but it landed a few feet in front of him, resulting in another double.

"The first one, I think he saw. It was just the communication without the practice out there," manager Bobby Valentine said. "The second one he didn't pick up."

At that point in the game, both teams were scoreless. In the middle of the fourth inning as Ciriaco was being replaced, television cameras spotted him up talking to first-base coach Alex Ochoa. Valentine approached them and joined the conversation, and the group was then seen laughing, appearing that Valentine had looked past the miscue.

Ciriaco went 0-for-2 at the plate with a strikeout. He is batting .294 with 15 steals in 66 games since being called up in early July.

Jacoby Ellsbury, who had played nine consecutive days and was out of the starting lineup, replaced Ciriaco.

Defensively, Ciriaco's played the infield well, too, committing eight errors and turning 17 double plays in 428 1/3 innings this season.

Iglesias caps three-hit night with first career homer

ST. PETERSBURG -- Lost amid the Red Sox's tough 7-4 walk-off loss to the Rays on Thursday night at Tropicana Field was the offensive performance turned in by rookie shortstop Jose Iglesias.

The 22-year-old went 3-for-4 at the plate and cranked his first career home run, raising his average from .057 to .128.

The ball was crushed to left field off reliever J.P. Howell in the ninth inning, giving Boston a 4-1 lead and nearly putting the game out of reach before Tampa Bay rallied in the bottom of the frame.

His other two hits were both singles off Rays ace David Price, eventually scoring on one of them.

"He had real good batting practice today, was very aggressive in batting practice and took it right into the game," manager Bobby Valentine said. "He swung at the first pitch twice and got a couple of singles. He swung hard and hit one out of the park."

Valentine added that Iglesias appears to be having a better approach at the dish.

"It seems like every game his confidence has been building, getting walks and having better at-bats," said Valentine, who before the game said Iglesias will see regular playing time as the season draws to a close.

Aviles returns to lineup, shifts over to hot corner

ST. PETERSBURG -- With Jose Iglesias seeing the bulk of playing time at shortstop recently, Mike Aviles returned to the Red Sox's lineup and shifted over to third base for the first time this season in Thursday's series finale vs. the Rays.

Aviles, who made 126 starts at shortstop, isn't completely unfamiliar to the position, starting 36 games at the hot corner in 2011 with the Royals and Red Sox.

"I asked Mike if he thought it'd be fair, and he said it was fine," manager Bobby Valentine said, not wanting to put Aviles in an uncomfortable spot. "It kind of makes it fair if he thinks it."

Aviles has been a rarity for Boston this year, being one of the few of the team's position players not to go on the disabled list. Being able to plug him in the lineup day after day has been a blessing for Valentine.

"He's played more than he's ever played, he's played consistently," Valentine said. "His defense has been, I think, amazing. His offense has been very productive. Obviously the walks aren't there, but he's gotten big hits, and he's hit good pitching, he's run the bases well."

In a career-high 133 games this year, Aviles is hitting .250 with 13 homers and 60 RBIs. Defensively, he's committed a team-high 14 errors.

Aviles hasn't seen as much playing time lately, and with the addition of Iglesias, sitting isn't "his cup of tea," said Valentine.

That doesn't take anything away from the way he's performed, though.

"He should be proud of the way he's played," Valentine said, "and I also am proud of the way he's played."

Atchison's back to old self since returning

ST. PETERSBURG -- A right elbow strain in July nearly ended reliever Scott Atchison's season, but the righty was able to rest up and return to the Red Sox.

Since Atchison's return from the 60-day disabled list Sept. 12, he's pitched well in 2 1/3 innings over two games, allowing no runs and one hit to go with a strikeout.

"He looks exactly the same," said manager Bobby Valentine. "As he's warming up, it's almost the same number of pitches, they're moving the same, it looks like the hitters are reacting to them the same."

Atchison had been one of Boston's better relievers before heading to the DL with an ulnar collateral ligament injury in his right elbow, compiling a 1.76 ERA in 46 innings with 34 strikeouts.

Perhaps more refreshingly for both Valentine and Atchison, it appears that a potential Tommy John surgery after the season might actually not be necessary.

"It looks like he can still do it," Valentine said. "Obviously somebody else will have to make that total determination. ... He's not acting through it, he's regular. There's no grimacing on his face."

Worth noting

• After falling 13-3 to the Rays on Wednesday for their 82nd loss, the Red Sox clinched their first losing season since 1997, when they went 78-84.

• Guillermo Quiroz became the 56th player to appear in a game for the Red Sox this season after coming in to catch in the seventh inning Wednesday. The appearance set a new club record, surpassing the 55 players Boston used in 1996.

Quiroz also saw his six-game hitting streak that stretched back to May 31, 2009, end when he struck out to end Wednesday's contest.