NEW YORK, NOV. 19 -- Top-seeded Steffi Graf advanced to the semifinals of the Virginia Slims tennis championships tonight when No. 7 Helena Sukova was forced to retire in the second set of their match because of a neck injury.

Sukova cried as she left the court, trailing, 6-2, 2-0.

The 6-foot-2 Czechoslovakian took a five-minute injury timeout after she fell behind, 5-2, in the first set. She returned after being treated by trainer Donna Pallulat and tournament physician Irving Glick, but was obviously still in pain.

A tournament official said Sukova had muscle spasms in her neck that caused pain in her left shoulder. She was treated with a heat pack after the match and was reportedly feeling better.

Graf's opponent in the semifinals will be Sylvia Hanika of West Germany, who defeated Raffaella Reggi of Italy, 6-2, 4-6, 6-0, earlier tonight. Hanika, who upset Chris Evert in the first round, won the battle of unseeded players by taking advantage of Reggi's weak serve.

The semifinal pairings will be completed Friday night when four-time defending champion Martina Navratilova plays No. 6 Gabriela Sabatini and No. 4 Pam Shriver faces No. 8 Manuela Maleeva.