DEERFIELD, Ill. (AP) Scottie Pippen is contemplating retirement because of recurring knee problems that have already kept him out of seven games.

Pippen is expected to miss his ninth game _ and fourth in a row _ when the Chicago Bulls travel to Milwaukee on Friday. He also missed a game after being poked in the eye.

``I question myself whether or not I can play another year. Or this year,'' Pippen said Wednesday after the Bulls practiced. ``I just have to wait and see.''

The 38-year-old Pippen missed 17 games last season after having surgery on his left knee. He returned for Portland's final two regular-season games and played 32 minutes in the playoff series opener. But he missed the rest of the postseason after the pain and swelling returned.

The Bulls have been cautious with Pippen's left knee, watching his minutes and his practice time. But the knee swelled after the first three games of the season, and he had to have it drained. He then missed four games.

The knee swelled again after the Dec. 1 game against Milwaukee. He has missed Chicago's last three games, and had the knee drained again Monday.

``I'm not going to say it's ominous, but it certainly isn't a positive sign when the fluid keeps returning,'' Bulls trainer Fred Tedeschi said.

``We're really not making the kind of progress we'd like to think we'd be making by now,'' Tedeschi said. ``We still have a problem with swelling, and we're investigating where we go from here.''

Asked if that meant more surgery, Tedeschi said the Bulls are exploring several options. And while no one said it specifically, retirement appears to be a possibility.

``Whatever determination they come to is fine,'' Bulls coach Scott Skiles said. ``I'd love to have him, but I've been an older player myself and understand there's nothing worse than being hurt all the time. It just gets to the point where, mentally, it's such a drag.''

A cornerstone of Chicago's championship run, Pippen was voted one of the 50 greatest players in NBA history in 1996. He's a seven-time All-Star in 16 seasons, and is one of the best defensive players ever.

When he signed a two-year, $10 million deal with the Bulls last summer, it wasn't out of nostalgia. He and general manager John Paxson hoped the forward could play at least 60 games, and give the young Bulls some desperately needed veteran leadership and experience.

``I don't know Scottie well, but I know him well enough at this point to know he's the consummate competitor. He doesn't want to spend time in the training room,'' Tedeschi said. ``He wants to be out there, and it is frustrating for him to not be able to do it.''