KANSAS CITY -- Veteran first baseman Mike Sweeney, who openly concedes he might be looking down the barrel of his final month in the big leagues, received a hero's welcome Tuesday when he arrived in the city in which he starred for the better part of 13 seasons.

He arrived as an inactive member of his current team, though, so his contribution to the A's was limited to presenting the lineup card to the umpiring crew at home plate before Tuesday's game.

"It was pretty exciting," Sweeney said Wednesday after the second game of a three-game series at Kauffman Stadium was postponed due to rain and rescheduled as part of a Thursday doubleheader. "It'll be more exciting when I get to step into the batter's box."

That could happen Thursday, because Sweeney became an active member of the A's Wednesday when he was reinstated him from the 60-day disabled list.

"It's a great place to come back," said Sweeney, whose five All-Star selections as a Royal are the third-most in franchise history. "I have a lot of friends here -- a lot of friends I consider family."

Getting one more chance to play in front of Royals fans, Sweeney said, was "a big part" of his motivation for returning from the DL.

He was placed on the 15-day DL with inflammation in his left knee on May 29, and on June 11 he underwent arthroscopic surgery on both of knees. Doctors told him he needs microfracture surgery on both knees, and that the recovery is six to nine months. He decided to try to get back on the field before submitting to surgeries that could very well end his career.

"There's probably a better chance of me not playing next year than there is of me playing," Sweeney said. "And if this is my last 30 days, I wanted to sprint to the finish line."

Sweeney, 35, started a rehab assignment with Triple-A Sacramento on Aug. 18. Widely regarded as one of the nicest men in the game, Sweeney said he thoroughly enjoyed his time with the River Cats, who opened the Pacific Coast League Pacific Conference Championship Series on Wednesday against visiting Salt Lake at Raley Field.

"It was humbling to see the hunger and rawness of the guys," Sweeney said. "A lot of them never played a day in the big leagues. They're playing for peanuts. They get one pair of cleats for the whole season, and the name on their bats is 'Pro Stock.'"

As a veteran big leaguer, Sweeney followed the unwritten rules of rehab assignments by paying for plenty of food for his younger, less financially fortunate teammates in Sacramento.

"I got 'em a lot of spreads," Sweeney said with a smile. "My financial advisor is going to be calling me when the bills start coming in."

In addition to providing food, Sweeney offered advice. When Josh Outman was told he'd be called up to the Majors a few days ago, Sweeney told the rookie about, among other things, the A's dress code that requires players to wear a collared shirt, nice jeans and dress shoes on the road.

Upon seeing Outman wearing tennis shoes on his first day with the A's, Sweeney found out that the young lefty didn't have enough money for new shoes.

"So my wife and I got him some nice shoes yesterday and sent them up to his room," Sweeney said. "His wife called and said, 'These shoes are so beautiful!' ... It's nice to be able to take care of the younger guys. Hopefully when they're in [the same position], they'll remember to do the same things."

A's manager Bob Geren said Sweeney will be a "part-time" player in September, seeing time at first base, designated hitter and as pinch-hitter. Sweeney, who was batting .292 with two homers and 12 RBIs in 40 games before being placed on the DL, seemed OK with that.

"I'm just going to try to enjoy every second of this last month, no matter what happens," he said.

To make room for him on the roster, Oakland transferred DH Frank Thomas (strained right quadriceps) from the 15-day DL to the 60-day DL, ending his season and possibly his career.

"Frank's obviously a Hall of Famer, a great man and a great teammate," Sweeney said. "You never know, if he wants to play, he could end up being the starting DH for the Oakland A's. He's certainly got the credentials. It's just a matter of if his health holds up."