Cal Ripken Sr., 63, began receiving chemotherapy treatments after doctors found a tumor on his lung.
His health has not improved, however, and the Orioles today excused Ripken Jr. from their exhibition game against the Montreal Expos in Jupiter, Fla., so he could be at his father's side in Baltimore.
"The Ripken family asks that the media respect their privacy at this difficult time," the Orioles said in a statement. "The thoughts and prayers of the Orioles organization are with the Ripken family."
Ripken Sr. enjoyed a 36-year-old association with the Orioles and had the pleasure of managing his son. The elder Ripken signed with Baltimore 1957 as a catcher but soon turned to managing, spending 14 years in the minors.
His teams finished first or second on seven occasions, and he joined the Orioles' coaching staff in 1976.
He was hired as manager in 1987, taking over a last-place team. He was fired in 1988 after an 0-6 start.
Ripken was the first man in the majors ever to manage two of his sons, Cal Jr. and Bill, who was the Orioles' second baseman at the time. The three Ripkens appeared on the cover of Sports Illustrated in 1987.
That year, Ripken Sr. replaced his son late in a game, ending Cal Jr.'s streak of 8,243 consecutive innings played.
Ripken Sr. was rehired as Orioles third base coach in 1989, but was fired after the 1992 season.
Until he became ill, Ripken Sr. ran the Cal Ripken Baseball School, a summer camp for children, at Mount St. Mary's College in Emmitsburg, Md.
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