``Today, I lost a dear friend and a coach,'' Sampras said from his home in Tampa, Fla. ``But we all lost a special person.''
Mr. Gullikson retired from the pro circuit in 1986 and made a successful transition to coaching, working with Martina Navratilova, Mary Joe Fernandez, Aaron Krickstein and Barbara Potter before teaming with Sampras in January 1992.
In the insular tennis world, where it is dangerous to make friends with a player you might draw tomorrow, and hard to make friends with anybody else, Mr. Gullikson and Sampras became more than teacher and pupil.
Mr. Gullikson was able to prod the nonchalant Sampras into short but intense practice sessions, and Sampras responded to Mr. Gullikson's soft voice, easy smile and wise advice. He became the dominant player on the men's circuit in 1994, winning two Grand Slams - the Australian Open and Wimbledon.
At the end of 1994, the first signs of Mr. Gullikson's illness emerged, and in January 1995, he made his last coaching appearance at the Australian Open, where Sampras was trying to defend his title.
Mr. Gullikson collapsed after a practice session with Sampras and flew home, accompanied by his brother. In the quarterfinals that day, Sampras burst into tears during a tense match against Jim Courier and played several games in between sobs.
He knew that Australian doctors had found that Mr. Gullikson had brain cancer and might have as little as three months to live.
When he got home to Wheaton, Ill., Mr. Gullikson's doctors told him the cancer was treatable. He began undergoing chemotherapy sessions, and for the rest of the year, Mr. Gullikson coached Sampras by phone.
While Sampras was winning Wimbledon, Mr. Gullikson watched at home. ``It was nerve-racking,'' he said of watching Sampras' Wimbledon final against Boris Becker. ``But I let out the loudest cheer when Pete won.''
Mr. Gullikson said that he planned to be back with Sampras at the U.S. Open last August, but he was never able to rejoin the tour.
``It's hard to have friends on this tour,'' Sampras said of their relationship, ``and I'm a very private person anyway. When Tim's not around, it's not just that I'm missing my coach. It's that I'm missing my best friend.''
Under Mr. Gullikson's teaching, Sampras went from being the sixth-ranked player in the world to being ranked No. 1 for nearly three years.
There will be a viewing Monday from 1-9 p.m. in Wheaton. Funeral services will be Tuesday at St. Michael's Catholic Church in Wheaton. The family asks that contributions be made to the Tim and Tom Gullikson Foundation, 8000 Sears Tower, Chicago, Ill. 60606.