CHICAGO -- A tip of the cap to Sean Marshall for a job well done. The Cubs' fill-in starting pitcher tossed the team's first quality start in a week.

Marshall went seven innings, surrendering three runs, five hits and one walk and striking out five in the Cubs' 5-1 loss to the White Sox on Sunday night. The lanky lefty succumbed to the long ball against the American League's top home run squad. Outfielders Carlos Quentin and Brian Anderson went deep in the fourth and fifth innings, respectively, to account for all of Marshall's earned runs.

Marshall's line would have looked better if not for counterpart Mark Buehrle's sightly night. The White Sox lefty gave up one unearned run in seven innings. Marshall (0-2) took the loss, but was proud nonetheless.

"I threw the ball well," Marshall said. "A little bit of improvement on a couple changeups I hung down the middle, but overall I thought that was a good game. Just turn the page and go to the next one."

There likely won't be a next start if Carlos Zambrano can come off the disabled list for Friday's game at St. Louis.

The Cubs still have a use for Marshall (0-2), with left-handed reliever Scott Eyre on the disabled list. Marshall could be available out of the bullpen in San Francisco as another lefty option opposite Neal Cotts.

He's also a candidate to be sent to Triple-A Iowa upon Zambrano's activation. If Sunday marked Marshall's last appearance during this big league stint, at least he went out with a strong performance.

He shut out the South Siders through three before Quentin sent the first pitch of the Sox fourth into the left-field stands. Marshall's leadoff walk to Nick Swisher in the fifth came back to bite him one out later on Anderson's two-run shot.

"A couple of mistakes, they made us pay for it," Cubs catcher Henry Blanco said. "Other than that, I think he pitched a real good game. You have to give him credit, too."

Marshall regrouped and retired six of the last seven batters he faced. Swisher singled to lead off the seventh, but was stranded at second base.

"We were hoping to get through the seventh," said bench coach Alan Trammell, who took over the managing duties after Lou Piniella was ejected in the second. "We thought he deserved to continue. It just seems like in the past, from what I've seen from Sean, is that sometimes he starts to labor a little bit in there. But I thought it was a good test for him. [Pitching coach] Larry [Rothschild] and I both decided that he earned the right to continue."