So far, the two have been up to the challenge.Dunn and Rios look to continue their hot hitting and lead the visiting White Sox to a fifth straight victory Tuesday night against the struggling Oakland Athletics.Chicago (10-6) finished in third place in the AL Central last season, 16 games back of division-leading Detroit, as its offense failed to live up to expectations. Dunn was at the center of the offensive woes, batting .159 with career lows of 11 homers and 42 RBIs, while Rios wasn't much better, hitting .227 with 13 home runs and 44 RBIs.While those two were major holes in the lineup a year ago, they're off to strong starts for a White Sox team that is tied with the Tigers atop the Central.Dunn hit his fourth homer in Monday's 4-0 win over the A's, and is batting .381 with three home runs, three doubles, 11 RBIs and a .536 on-base percentage in his last six games. He didn't hit his fifth homer last season until May 24.Rios is also locked in at the plate, recording his second straight three-hit game Monday. He is batting .415 with three doubles and six RBIs during an 11-game hitting streak.In spite of Dunn's strong start, he is still having loads of trouble facing left-handed pitchers, batting .056 with 10 strikeouts in 18 at-bats -- numbers that could lead to problems against Tommy Milone (2-1, 2.84 ERA).Chicago counters with Gavin Floyd (1-2, 4.58), who hopes to bounce back from another shaky outing.Floyd gave up five runs, six hits and three walks while striking out seven over six innings in Thursday's 5-3 loss to Baltimore. The right-hander, who failed to last more than six innings in any of his first three starts, hit one Oriole after plunking three batters in his previous outing.He is now set to face an Oakland offense having several problems of its own.The A's (8-10) managed just three hits against Jake Peavy on Monday in losing for the fourth time in five games. They're last in the AL with 52 runs, are hitting a league-low .205 and have been held to one run or fewer seven times. Catcher Kurt Suzuki is in the middle of this mess batting .186, while Coco Crisp, who returned to the lineup Monday after missing five games with the flu, is hitting .167."We're on and off, on and off," said leadoff hitter Jemile Weeks, who is batting .200. "If we can get some back-to-back (offensive) days going, I think we'll be more fluent in our offense."The A's also had one of the AL's worst offenses last season, but still managed to give Floyd trouble.In his lone start of 2011 against Oakland, Floyd allowed five runs and nine hits in 4 1/3 innings of a 6-2 loss May 14. He was 3-0 with a 1.32 ERA in his first six career outings versus the A's.Milone continued his impressive start Thursday against Los Angeles, yielding two runs and seven hits in five innings of a 4-2 win. The left-hander struck out three and walked one.This will be Milone's fourth start of the season after appearing in five games last year for Washington before coming over as part of the Gio Gonzalez trade.