Cardinals send Wacha to the bump a day ahead of schedule

The Chicago White Sox's surge heading into the All-Star break prompted general manager Rick Hahn to be coy about his plans prior to the trade deadline.

He's going to have a more difficult time putting off decisions after the White Sox dropped three of four to open the second half, leading to more speculation that changes could be imminent.

The MLB-best St. Louis Cardinals are in a much more comfortable position as they begin a two-game series in Chicago on Tuesday night.

The White Sox (42-48) won nine of 12 heading into the break, and Hahn wouldn't commit to being a seller at the deadline or taking a shot at what appears to be an unlikely run at a postseason spot.

Chicago has scored fewer than three runs in four of its last five and fell 4-1 to AL Central-leading Kansas City on Sunday -- the seventh time they've lost when Chris Sale pitches.

Manager Robin Ventura is trying to limit the distractions with the July 31 deadline approaching.

"I know everybody wants to talk about (trade rumors), but we're going to play as hard as we can against St. Louis," Ventura said.

The White Sox began their strong finish to the first half with a pair of wins against the Cardinals, earning a 2-1, 11-inning victory June 30 before sweeping the series with a 7-1 win the following night.

St. Louis (58-34) has gone 7-10 since the start of that set but still possesses the best record in baseball. It won the first two of its weekend series against the New York Mets before losing Sunday's 18-inning marathon 3-1.

Kolten Wong's homer in the bottom of the 13th tied it before the Mets scored twice off Carlos Martinez in the final inning. Martinez originally was scheduled to start this game but was forced to pitch four innings after the Cardinals ran out of available relievers.

"We were trying to stay away from Martinez, but it got to the point where it was not possible," manager Mike Matheny said.

That means Michael Wacha (10-3, 2.93 ERA) will move up one day to start this matchup. Wacha had a rough road outing against the Chicago Cubs in his last start July 8, allowing a season high-tying five runs in six innings before the Cardinals rallied for a 6-5 win.

The right-hander went 7-0 with a 1.87 ERA over his first nine starts, but he has a 4.17 ERA over his last eight.

Rookie Carlos Rodon (3-2, 3.80) opposes Wacha looking to get a grasp on his control.

Rodon allowed two hits over six innings of the White Sox's 1-0 win over the Cubs on July 10, but he tied a season high with six walks. He's walked at least three in four straight starts, and his 5.56 walks per nine innings are the worst in the majors among pitchers with at least 66 innings.

The left-hander has allowed eight first-inning runs over his last five starts, and the White Sox have given up a run in the first in four of their last five. Chicago's 72 runs allowed in the initial inning are among the most in baseball.

The Cardinals' .257 average ranks in the top 10 in the majors, but they're hitting .218 in eight games in AL parks. Top prospect Stephen Piscotty is expected to make his major league debut in this series, possibly at designated hitter.

Outfielder Jason Heyward could return to the lineup after sitting out Sunday because of a head cold and dehydration.