CHICAGO -- Manager Mike Quade finds the Cubs remain a work in progress after a 3-5 homestand, dropping two of three to division rivals Cincinnati and St. Louis.
"The truth of the matter is if you take two out of three from those clubs, it's a huge difference," he said. "But you have to take them. We're not there yet. That's a fact."
The Cubs also split two weekend games with the defending World Series champion Giants, but rain forced postponement of Sunday's series finale.
The game will be made up at 1:20 p.m. on June 28 at Wrigley Field as part of a day-night doubleheader.
In the five losses, the Cubs left 45 men on base and went 7-for-43 with runners in scoring position.
"My sense is that there were more missed opportunities to score runs than anything else," Quade said. "If we're going to continue to struggle and if run production is going to be an issue right now, we need to play perfect baseball in other areas."
Before the rainout, Quade had shuffled his lineup a bit in preparation for Giants ace Tim Lincecum (3-3), giving Marlon Byrd and Alfonso Soriano a day off while moving Blake DeWitt into the No. 5 spot and Reed Johnson sixth.
Tyler Colvin's early-season struggles could lead to a trip to Triple-A Iowa.
"He's not going to get out of his funk by a pinch-hit here and there and a game once a week," Quade said. "We have a lot to think about as far as that goes."
Colvin has seen little playing time, managing just seven hits in 62 at-bats, a far cry from his 20-homer breakout season in 2010.
"Last year I didn't get a lot of at-bats early, but I made the most of it. This year I'm not doing that," Colvin said.
Carlos Zambrano (4-1), who was set to start Sunday, will pitch Monday in Cincinnati instead.
The Giants won 3-0 in a rain-shortened game Saturday.
Despite the rainout, Quade plans to keep his rotation intact. Matt Garza will pitch Tuesday, Ryan Dempster and Casey Coleman will face the Florida Marlins in a two-game set, then recently promoted Doug Davis will start the series opener in Boston. ... Sunday's postponement was announced before Wrigley Field's gates opened. Conditions did not improve as the originally scheduled 1:20 p.m. game time approached with steady rain. ... The Cubs open a seven-game road swing Monday that takes them to Cincinnati, Florida and Boston. They return to Wrigley Field on May 24 for a three-game series against the Mets.