The Sovran Bank Classic receded to the predicted and the predictable yesterday. The top remaining seeds -- Andre Agassi, Brad Gilbert, Michael Chang and Jim Grabb -- advanced to today's semifinals with straight-set wins at the William H.G. FitzGerald Tennis Center in Rock Creek Park.

And, even a day after his departure from the tournament, John McEnroe was a leading topic of conversation -- this time for his prognosticative powers, which proved uncanny when two-time conquerer Derrick Rostagno returned to uninspired form.

Gilbert faces Grabb at 1, with Agassi and Chang to meet at 7. In a tournament billed as a showcase of the top Americans, all the survivors are Americans.

Top-seeded Agassi survived five set points and a tiebreaker in the first set to storm past Richey Reneberg, 7-6 (7-4), 6-0. Reneberg's set points came on Agassi's serve during a nine-deuce 12th game that Agassi finally won with a brilliant forehand drop shot from far wide of the sideline that prompted him to raise his arms in celebration and bow to the crowd's raucous ovation.

Agassi won the last three points of the tiebreaker, finishing it with a backhand volley after moving to the net behind a moonball approach shot. He then exploded with a breathtaking display of shot making while Reneberg sagged in the anticlimactic second set.

"I felt like I lost some concentration in the second set," said Reneberg, the seventh seed, "and before I knew it, it was 4-0. He keeps the pressure on you. You can't relax, and I relaxed a little bit."

Agassi's first-set stand began after he dug himself a 5-6, 15-40 hole. He saved two set points with a testing serve and backhand volley, later surviving two set-point, second-serve chances for Reneberg.

"Even at that point, I was still pretty sure I'd get him in the long run," Agassi said. "I knew as the match went on the more into it I'd get."

Chang, seeded fifth, outlasted No. 14 Todd Witsken, 6-3, 6-4, in a battle of ground strokes, patience and fortitude. Witsken had upset 1989 champion Tim Mayotte Thursday.

Chang, in claiming his third consecutive straight-sets victory this week, used a break in the eighth game to capture the first set, then took the match by winning Witsken's final two service games.

"I've had a good tournament, and hopefully it will get better still," said Chang, who has beaten Agassi twice in exhibitions but is 0-3 against him in tournaments, including a four-set loss in the quarterfinals of this year's French Open.

"I think I have to take more chances {against Agassi}. I have to go into the net and mix it up a little bit. . . . It's very difficult to play Andre from the back."

Less spectacular but still productive was Grabb, a steady hard-court specialist who hasn't lost a set in the tournament. He used an unanswered service break in each set to beat error-prone Rostagno, 6-4, 6-3.

After Rostagno beat him Thursday night for the second time in less than four weeks, McEnroe took a swipe at Rostagno's erratic nature by predicting he would lose yesterday. Rostagno is capable of scaring anyone and came within a miraculous net cord of ousting Boris Becker from the 1989 U.S. Open.

But he still came here as the 113th-ranked player, and his reputation as one of the game's leading eccentrics includes the rap that he never has utilized his considerable talent.

"Derrick is one of the most unpredictable players on the tour," Gilbert said in assessing his possible opponents before the Rostagno-Grabb encounter. "He could play a great match or a terrible one. . . . He's one of the few relatively lower-ranked guys who plays better against the top 15 players."

Rostagno found it difficult to dispute the split-personality characterization after losing to Grabb, his former teammate at Stanford.

The Rostagno of yesterday did not resemble Thursday's high-intensity, serve-and-volley terror. He lost his concentration after several debatable line calls in the first set. He was broken by Grabb in the last game of the first set and in the sixth game of the second for a 2-4 deficit.

Rostagno had only three break points and lost all of them. Sixth-seeded Grabb played mistake-free tennis; Rostagno's would-be winners fell tantalizingly wide or long.

"I just wasn't strong enough mentally," Rostagno said. "I was letting things bother me, like the line calls. . . . When I get really excited to play a match, I'm just really focused. {Yesterday} I wasn't focused enough. I gave him one game each set, and that was the match. . . . Jim was playing well and holding his serve, but if I played better we might still be out there, on serve."

Second-seeded Gilbert played his best tennis of the week in the day's first match to beat Michael Stich, 6-3, 6-4. He was in control throughout, changing pace on his shots smartly and moving Stich around in the unforgiving heat, as on-court temperatures topped 100 degrees early in the afternoon.

"It's very difficult to play him," Stich said. "The harder you hit the ball, the tougher he gets. . . . You say you should be able to beat him, but the better you play, the better he plays."

That is the essence of Gilbert, the world's No. 6 player who gets by on grit and a thoughtful, workmanlike style that doesn't approach the flash of those ahead of him in the rankings. His volleys often aren't particularly crisp, his serve doesn't overwhelm.

But he is a constant nuisance, and he has become the summertime demon of the tour. Gilbert lost in the first round of both Wimbledon and the U.S. Open last year, but won 23 of 24 matches in between. He already has begun to construct a solid 1990, with two titles and a quarterfinal showing at Wimbledon that lends hope to his bid to improve upon a history of Grand Slam failings at the U.S. Open next month.

"This is my time of the year," he said. "This is my surface, and I think I'm playing really well right now. . . . I felt like I should have won here last year {when he was runner-up to Mayotte}, and I thought I had a good chance in '87 but {Ivan} Lendl was on top of his game and just flattened me" in the final.