CHICAGO -- Alex Rios did not get off to the start he hoped for in 2008, but he's making up for it in a big way in the second half, particularly with his power stroke.

"This is the best I've felt since the beginning of the season," Rios said before Monday's rained-out contest against the White Sox. "I've been more aggressive in the strike zone, instead of swinging at bad pitches and getting myself jammed. That's a big part of it."

Rios was batting .270 with a .328 on-base percentage and a .372 slugging percentage on June 20, the day John Gibbons was replaced by Cito Gaston as manager. All of those numbers have risen substantially since Gaston took over, most noticeably his .566 slugging mark.

Rios was named the American League Player of the Week on Monday for the first time in his career. He earned the honor by batting .414 in six games and leading the AL in extra-base hits with eight, including three home runs.

To put that into perspective, Rios had only hit four homers through June 30. He hit that many in July alone and has added five more since.

"I could have got better power numbers, but I'm looking just to finish strong here," Rios said. "The first half of the season doesn't matter anymore. It's already gone, so I just have to focus on right now."

Many believed a 30-30 season was in store for the speedy outfielder, but such goals don't interest Rios, who already has reached 30 stolen bases this season, nearing double the 17 he swiped a year ago.

"I don't put any personal goals on myself," Rios said. "I just go with the flow. Whatever happens, happens. It feels good that they let me run, because I help the team stealing bases. So it was a good thing that they give some of the guys the green light."