CHICAGO -- White Sox manager Ozzie Guillen still isn't sure exactly what type of team he has on his hands, as it prepares for a playoff push over the final six weeks of the regular season.

What he does know is that he didn't like the group that showed up at U.S. Cellular Field on Sunday afternoon, a White Sox squad that produced just seven hits and lost, 5-4, against the American League East's last-place Orioles.

"I think today was a very, very, very disappointing game for me," Guillen said. "I always talk about pitching and defense. With the offense we have, we're better than this. We have a month and a half to go, and if our offense continues like that, good luck. It's going to be hard for us to be there in the end."

In winning on Sunday, Baltimore took two of three games this weekend and finished with a 5-4 record in the season series over Chicago, capturing just its second season series in the last 10 years against the White Sox.

Overall, Chicago closed out a 3-3 homestand against Baltimore and Kansas City, also a last-place team in the AL Central.

"Obviously, you want to go out and play a Kansas City and Baltimore. I mean, we'd like to take two of three or go out and sweep them," starter Mark Buehrle said. "But they're good young teams. They've got good hitting, good pitching. It's just one of those things that happens."

On Sunday, Buehrle filed an unspectacular pitching line, lasting 5 1/3 innings and allowing five runs on 11 hits with four strikeouts. It marked the third time in his last six games that he has allowed double-digit base hits.

Since throwing the 18th perfect game in Major League history on July 23 against Tampa Bay, Buehrle is 0-4 in six starts with a 6.21 ERA. During that time, he has allowed 54 hits over 37 2/3 innings.

"It seems like lately I'm making some pitches and they're finding some holes, and then when you're making a mistake, they're hitting the ball hard," Buehrle said. "It's just one of those little funks I'm in. Obviously, I need to come out of it sooner than later."

Even though Buehrle (11-7) was not at his best, he still kept his team in the game for the duration of his stint on the mound, leaving the game in the sixth with his team trailing just 5-3.

The Orioles broke a scoreless tie just three batters into Sunday's game, when Adam Jones looped a single off the end of his bat into left field, scoring Brian Roberts for an early 1-0 Orioles lead.

Chicago snatched that run back in the bottom of the first, thanks to a couple of defensive miscues by Baltimore. Scott Podsednik reached base on shortstop Robert Andino's fielding error and stole second. Podsednik scored on the very next batter, when third baseman Melvin Mora threw wide of first on Gordon Beckham's grounder. The ball carried into the visiting dugout, allowing Podsednik to take home for a 1-1 tie.

But the Orioles (51-73) distanced themselves from the White Sox in the top of the third with a three-run frame off Buehrle. Roberts scored on a sacrifice fly to left from Felix Pie, who entered the game in the bottom of the first after Jones suffered a mild spasm in his back. Following a Nick Markakis single, Nolan Reimold clubbed the first pitch he saw 384 feet into the left-field seats, a two-run homer that put the Orioles ahead, 4-1.

Roberts finished Sunday's game 3-for-4 with a double and two runs scored, all off Buehrle.

"With [Buehrle], obviously, if he leaves balls over the plate and guys actually take advantage of it, it hurts him," Roberts said. "He gets away with some sometimes, just because of the fact that he mixes pitches pretty well and uses both sides of the plate. Today, we got a couple balls up and were able to capitalize."

The White Sox offense, however, was not able to capitalize, even though it was facing Orioles starter Jason Berken, who entered the game with a 2-11 record, a 6.72 ERA and a name that Guillen couldn't remember after the game.

Berken (3-11) lasted 5 2/3 innings, allowing three runs (two earned) on five hits.

It wasn't until the bottom of the ninth inning that the White Sox offense made some noise that brought the crowd to its feet.

With Orioles reliever Jim Johnson in to close the game, Paul Konerko led off with a double to left-center field. He moved to third when Alexei Ramirez singled through the right side with one out. That brought up pinch hitter A.J. Pierzynski, who rolled a slow grounder to short, allowing Konerko to score to trim the deficit to 5-4. But pinch-hitter Mark Kotsay struck out swinging to end the game, and Johnson was able to pick up his sixth save.

"If you score three runs in eight innings, it's going to be tough to score three runs in one," Guillen said.

Guillen will attempt to solve the enigma that is his offense over the next week and a half during a crucial stretch of games, when the White Sox travel to face Boston, New York and Minnesota for 10 contests.

Guillen did not appear nearly as optimistic following Sunday's offensive output as he had been before the game.

"With the offense we have, we're better than this," Guillen said. "And we're going to face the big boys in two days? Good luck."

Both Konerko and Buehrle admitted afterward that the White Sox (63-61) upcoming road trip may not make the season, but it certainly could break the season.

"Hopefully, we can go at least .500 or better," Buehrle said. "I think if we go under .500, it's going to be tough to dig ourselves out of a hole."