BERLIN (AP) -- Jennifer Capriati is getting this comeback routine down pat.

Capriati needed two hours to pull out a thrilling 2-6, 6-3, 6-4 victory against defending champion Conchita Martinez at the German Open on Friday after losing the first four games of the match, then coming within a point of trailing 0-3 in the final set.

Ranked fourth in the world, Capriati finally reached the semifinals by whipping a forehand into the open court, but not before the former Wimbledon winner had tested her with every slice, volley and high ``moon ball'' in her repertoire.

``It was definitely physical and tiring. Maybe a year ago I wouldn't have been that mentally tough,'' said Capriati, who has made an amazing comeback from tennis obscurity this year.

It was the best match so far at the $1.185 million clay court event, which started with three of the world's top four players until No. 2 Venus Williams was upset Thursday.

Top-seeded Martina Hingis also won, besting Arantxa Sanchez-Vicario 6-3, 7-6 (4) to gain a measure of revenge for a straight-sets loss to the Spaniard last month at Amelia Island, Fla.

In other quarterfinals, Belgium teen-ager Justine Henin defeated German wild card entry Miriam Schnitzer 6-4, 6-2 and France's Amelie Mauresmo ousted South Africa's Amanda Coetzer 6-7 (5), 6-3, 6-3.

In Saturday's semifinals, Capriati will face Henin, while Hingis will take on Mauresmo.

Capriati, ranked sixth in the world in 1990 when she was 14, and the 28-year-old Martinez, who reached the French Open final last year, engaged in long crowd-pleasing rallies as each tried to probe the other, looking for an opening. The Spaniard tried drop shots, overheads and volleys as she tried to keep Capriati off-balance.

``It just proves to me I can beat the top players on clay,'' Capriati said. ``I've played her many times before, but I think she played well. It definitely demanded patience and know-how in deciding to go for a winner.''

Henin, ranked 18th in the world, upset Williams in the previous round and is looking forward to playing Capriati.

``I'll go out there and do my best -- I have nothing to lose. But I am thinking of winning the event,'' said Henin, who opened the year by winning two tournaments.

Hingis let a 4-2 third-set lead against Sanchez-Vicario slip away, then rattled off the last three points of the tiebreak to beat the three-time French Open winner for the 16th time in 18 meetings.

The 20-year-old Swiss star said she is gaining confidence with every match since making a break last month from her mother, who no longer guides her through every tournament as her coach.

``Oh, definitely. It feels like the good old days, except I'm doing everything myself,'' said Hingis.

Capriati, chasing her second straight title after Charleston two weeks ago, kept alive her streak of reaching the semifinals of every event since she won the Australian Open in January. In both of her tournament victories, she beat Hingis in the final.

Martinez won this tournament in 1998 and last year. She appeared to have Capriati in serious trouble by racing to a 4-0 first-set lead before the American could adjust to the Spaniard's slices and sharply angled shots, mixed with the high topspin ``moon balls'' that backed Capriati up almost against the retaining wall.

But then Capriati grew more patient and began to pressure Martinez with precise shots, occasionally lashing winners down the line.

Hingis dominated Sanchez-Vicario until the Spaniard raised the level of her game in the second set, but the Swiss star won the points when it counted.

``The score was closer than it said in the end, but the top players win those points,'' Hingis said.