KANSAS CITY, Mo. – Chicago White Sox designated hitter Adam Dunn underwent an emergency appendectomy Tuesday night and will miss at least five games.

The team said Dunn felt discomfort during Kansas City’s 7-6, 12-inning victory Tuesday and was taken to a hospital after the game. He was expected to travel with the team to Chicago after a Wednesday afternoon game.

Dunn scored a run and was 0 for 4 with a walk and a hit-by-pitch against the Royals.

Dunn is hitting .286 with one home run and needs 45 homers to reach 400. The offseason acquisition signed a four-year, $56 million contract with the White Sox.

The Kansas City Royals defeated the Chicago White Sox, capping a 12-inning marathon on Tuesday night. On Wednesday the White Sox will look for revenge after a short turnaround.

The White Sox and Royals are slatted to play at 1:10 (CST), roughly 14 hours after ending their Tuesday game.

Kansas City (4-1) lost its season opener, but it has shown a flair for late-inning dramatics since.

The Royals won for the third time on a walk-off hit and for the fourth time in their final at-bat after Melky Cabrera’s RBI single in the 12th inning lifted them to a 7-6 win over the White Sox (2-2) on Tuesday.

“These first five games have been the funnest five games I ever played in my life,” said Billy Butler, whose two-run homer tied it 6-all in the eighth. “Hopefully we can get off to a good lead and just cruise to a victory.”

It was Kansas City’s second straight win in extra innings. On Sunday, Matt Treanor hit a three-run homer with two outs in the 13th of a 12-9 victory over the Angels.

While the Royals, who haven’t won five in a row since Sept. 7-11, 2009, are hitting well under pressure, White Sox relievers continue to struggle late in games.

Chris Sale blew a save opportunity and Tony Pena took the loss Tuesday. Chicago’s bullpen has given up 14 runs, 22 hits and three home runs in 12 1-3 innings.

The White Sox will try to earn a split of the series before heading home as they hand the ball to Mark Buehrle (1-0, 6.00 ERA), who received plenty of support in his first start.

The left-hander gave up four runs and eight hits in six innings of a 15-10 win over Cleveland on Friday. At one point, the White Sox led 14-0.

“You’d love to get that many runs, but you know it’s not going to happen every time,” he said.

Buehrle would appreciate some support against the Royals after he went 1-2 with a 3.76 ERA in four starts against them last season. Chicago scored one run while he was on the mound in three of those starts.

Buehrle, who lost both visits to Kauffman Stadium, is 21-11 with a 3.57 ERA in his career against Kansas City.

He’ll try to cool off Melky Cabrera, who had three hits and three RBIs Tuesday and is hitting .325 with 14 extra-base hits against the White Sox. Cabrera, though, is 8 for 14 with a double and a home run against Buehrle.

The Royals will counter with Jeff Francis (0-0, 1.29), who was impressive in his Kansas City debut, giving up five hits, including a solo home run, over seven innings of Friday’s 2-1 victory over the Angels.

The 30-year-old missed the entire 2009 season and part of 2010 after surgery on his throwing shoulder. He went 4-6 with a 5.00 ERA with the Rockies last year.

The left-hander is 0-1 with a 6.75 ERA in two starts against the White Sox. This is the first time he’s faced them since 2008.

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