Silva, who won his first eight decisions of the season, lasted just one inning against the Astros last Monday, as he was pounded for five runs and seven hits to fall to 9-4 on the year. He wasn't able to get out of the second inning in his previous outing and has given up 11 runs in his last 2 1/3 frames to raise his earned run average to 3.86.
"He's not as sharp as he was earlier, that's for sure," Cubs manager Lou Piniella said. "We have to get him straightened out.
The 31-year-old righty is 2-1 lifetime against Houston with a 5.40 ERA in eight games, three of which have been starts.
Chicago was denied a sweep in its weekend set with the St. Louis Cardinals, falling in heartbreaking fashion on Sunday, as Felipe Lopez's 11th-inning home run propelled the Cards to a 4-3 win.
Ryan Theriot and Marlon Byrd each had two hits and a run driven in for the Cubs, who nonetheless claimed their first series win against a division foe since sweeping Milwaukee from April 23-25, a string of 10 series.
The Cubs had ample opportunity to pull off the sweep, but went 2-for-13 with runners in scoring position. Included was an 0-for-10 performance in their final 10 chances with runners aboard.
Houston, meanwhile, avoided a sweep at the hands of the Cincinnati Reds on Sunday, as Wandy Rodriguez spun seven innings of one-hit ball and received home run support from Hunter Pence and Chris Johnson in a 4-0 win.
Rodriguez (8-11) walked two, struck out seven and did not allow a runner past first base in leading Houston to its' first win in six tries against the Reds at Minute Maid Park this season.
Trying to keep the Astros in the win column this evening will be left-hander Wesley Wright, who will be making his second start of the season. Wright did not get a decision on Tuesday against the Cubs, but gave up six runs - one earned - and six hits in just 4 2/3 innings of his team's 14-7 setback.
Wright, who has pitched to a 4.40 ERA without earning a decision this season, is 2-0 with a 4.11 ERA in 14 games against the Cubs. Tonight's assignment, though, will be just his second start against the club.
Houston has won six of its nine matchups with the Cubs this season.