Chet Lemon, who played for the Detroit Tigers and Chicago White Sox, was in serious condition early today in a Florida hospital for a blood-clotting disorder, Tigers officials said.

Lemon, released from the Tigers in April after nine years with the club, reportedly was suffering from a severe blood-clotting problem in his abdomen, Greg Shea said.

"The doctors are not certain what caused it. They're looking into a variety of things, but whatever it is, it's a rare disorder," Shea said.

Lemon, 36, who has lived in Lakeland, Fla., since leaving the Tigers, was in Shand's Hospital at the University of Florida in Gainesville, Shea said. He was hospitalized about two weeks ago.

* BO KNOWS FRUSTRATION: Bo Jackson is gradually working himself back into major-league form.

It's not so much that Jackson has five hits, all singles, in 15 at-bats since beginning a minor-league rehabilitation program. It's that he's beginning to show the frustration that comes when his club is struggling.

In this case, the team is Double A Birmingham, which is in the throes of a five-game losing skid. Jackson has been with the club the last three nights and twice has endured shutout losses.

In his final at-bat last night, Jackson popped out to short leading off the ninth. As he ran toward first, Jackson snapped the bat over his right knee.

The Barons' locker room "was not a happy place," a club official said, and Jackson eschewed his usual post-game news conference.

In a statement released through the club, Jackson said, "I feel fine. Other than that, it was just another night of rehabilitation."

Jackson went 1-for-3 with a walk last night as Birmingham was beaten 3-0 by Jacksonville. Jackson singled to short in the first inning, struck out in the fourth and walked in the sixth before popping to short.

A crowd of 8,305 was on hand for last night's game, about twice the Barons' average but the smallest in the three days Jackson has been with the team.