Steffi Graf Amelia Island final on clay, Graf lost her first match of the year to Sabatini but returned to European clay with easy victories at Hamburg and Berlin. Graf's Grand Slam tournament winning streak ended at the French Open, where 17-year-old Spaniard Arantxa Sánchez Vicario beat Graf in three sets. Graf served for the match at 5–3 in the third set but lost the game and won only three more points in the match. Suffering from food poisoning, she had struggled to beat Monica Seles in their semifinal 6–3, 3–6, 6–3 and said that she had had menstrual cramps in the
Steffi Graf consecutive weeks, a record (it was tied by Serena Williams in 2016). Graf was the first player other than Navratilova or Evert to hold the top spot since Tracy Austin in 1980. Graf started 1988 by winning the Australian Open, defeating Chris Evert in the final 6–1, 7–6. Graf did not lose a set during the tournament and lost a total of only 29 games. Graf lost twice to Sabatini during the spring, once on hardcourts in Boca Raton, Florida, and once on clay at Amelia Island, Florida. Graf, however, won the tournament in San Antonio, Texas, and retained her