Injured Japanese right-hander Masumi Kuwata is likely to need up to six weeks before returning to action, effectively leaving him out of the Pittsburgh Pirates' opening-day roster, club officials said Tuesday.
Pirates General Manager Dave Littlefield said the latest tests showed no broken bones or torn ligaments in Kuwata's right ankle.
Kuwata was taken off the field after colliding with home plate umpire Wally Bell when he tried to back up third base in the eighth inning of a game Monday against the Toronto Blue Jays.
Littlefield added he will meet with Kuwata on Wednesday to discuss his future.
The tests the 38-year-old veteran received Monday and Tuesday both confirmed he has a grade 3 sprain, the severest of three types.
Kuwata is 0-0 with a 4.05 earned-run average in five spring training games with the Pirates.
Last fall, Kuwata decided to leave the Yomiuri Giants after 21 seasons with the Tokyo club, which had left him out of its plans for the 2007 season.