CHICAGO (AP) — Zack Greinke's second start with the Houston Astros has been postponed by rain.The Astros were scheduled to begin a three-game series against the Chicago White Sox on Monday night, but the rain started to pick up in the afternoon and the game was quickly called.The teams will play a traditional doubleheader Tuesday. Greinke and Gerrit Cole will pitch for Houston, and rookie Dylan Cease and Iván Nova are the scheduled starters for Chicago.The 35-year-old Greinke was acquired in a blockbuster trade with Arizona on July 31, giving Houston another ace for its rotation. The six-time All-Star got the win in his Astros debut, pitching six innings of five-run ball in an 11-6 victory over Colorado on Tuesday.Houston has won 12 of 15 to open a 10-game lead in the AL West. It looked as if it was headed for its ninth straight win Sunday in Baltimore, but Roberto Osuna surrendered a two-run homer to Rio Ruiz with two out in the ninth inning of the Orioles' 8-7 victory.Houston's pitching staff could get a lift when Brad Peacock returns after being sidelined by right shoulder discomfort. He made two rehab appearances for Triple-A Round Rock over the weekend, but he failed to record an out Sunday and was charged with four runs.Manager A.J. Hinch said he hadn't talked to anyone about Peacock's work Sunday and wasn't sure when he might be rejoining the team.Chicago dropped two of three against Oakland over the weekend. Lucas Giolito struck out a career-high 13 in six innings Sunday, but Matt Olson homered for the Athletics and the White Sox were shut down by Chris Bassitt in a 2-0 loss.The 23-year-old Cease was slated to get the ball on Monday. The right-hander had dropped four consecutive starts before he pitched five effective innings in a 5-3 win at Detroit last week."What we've seen with Dylan is trying to get him to be more efficient, be more confident early, attack early, trust the stuff that he has," manager Rick Renteria said. "I think his command is one of the things we've been trying to work on. It was still something that we were dealing with before we brought him up. ... He's got a chance to be really good."The Astros are closing in on their third consecutive playoff appearance. They are among the favorites to win the World Series after taking home the title in 2017, and Renteria said his young ballclub can learn from how the Astros play."I think we use every really good club that we play as an example," he said. "You look to see what are the things that they're doing, what are the skill sets that they bring to the table and how can we emulate. But you want your team to be themselves, as well."___Jay Cohen can be reached at https://twitter.com/jcohenap___More AP MLB: https://apnews.com/MLB and https://twitter.com/AP_Sports