Jimmy Connors wasn't really sharp last night, but when you're the sixth-ranked player in the world, dull usually wins.

Connors defeated Kelly Jones of San Diego, 6-3, 6-4, in the second round of the Sovran Bank/D.C. National Tennis Classic at Rock Creek Tennis Center before a capacity crowd of 5,500 at stadium court.

The tournament, which lost five seeds to defeat in the first two days of play, lost another last night, this one to injury. Sixth-seeded Aaron Krickstein of Grosse Pointe, Mich., was diagnosed as apparently having a stress fracture of the left leg. An initial prognosis is for Krickstein to be sidelined four to six weeks.

Craig Miller of Australia will take Krickstein's place in the draw as the "lucky loser," the highest-ranking available player who lost in the qualifying tournament.

Connors actually fell behind, being broken in the opening game and trailing, 2-0, after Jones held serve. But from 1-3, he won three straight games.

"The court is a little bit bumpy and rocky at places," Connors said of the new hard court surface. "It was difficult to feel I was getting a real solid hit at the ball.

"Some of the ground strokes were sailing off on me. It's not me. I don't think it's me. {But} the court surface is good. I like it."

In game eight of the first set, Connors got to 30-0 following Jones' double fault. At 15-30, Jones netted a backhand half-volley.

Connors then hit a nice lob over Jones, who managed to return it with a behind-the-back flick of the racket. Connors, though, covered the net for the putaway and a 5-3 lead.

In game nine, Jones got within a point of breaking back at 0-40 when Connors' smash caught the net and fell back into his court.

But Connors smashed off Jones' defensive lob for 15-40, Jones' forehand went long for 30-40, and a service winner brought Connors to deuce. Jones missed a chance for advantage when he mis-hit two slams near the net.

Jones said he finessed the first slam after he saw Connors. "I thought he had given up the point," he said. "I don't know what happened. I was going to hit it over the fence, which I should have done."

Connors reached advantage when Jones' drop volley hit the net. Connors closed out the set with a sharp forehand that Jones could only net.

Connors broke in the fifth game of the second set, aided by Jones' two double faults. He won the game with a backhand down the line that Jones barely got his racket on.

Connors held for 4-2, acing on the second serve at 40-30, and Jones held for 4-3.

Jones said he didn't hit his forehand as well as he usually does, and didn't attack the net.

"I wasn't going to win points on the base line," he said. "Basically, I had to attack and make him hit the shot."

Earlier in the day, seventh-seeded Jimmy Arias of Jericho, N.Y., beat Michael Kures of Willow Springs, Ill., in a second-round match, 7-5, 6-2. In first-round play, 12th-seeded Todd Witsken of Carmel, Ind., had little trouble defeating Ken Flach of Sebring, Fla., 6-2, 6-1; 13th-seeded Nkuda Odizor of Nigeria eliminated Gary Donnelly of Scottsdale, Ariz., 6-3, 6-2, and 14th-seeded Jim Pugh of Palos Verdes, Calif., dispatched Derek Tarr of Birmingham, 6-2, 6-1.

No. 11 Jaime Yzaga of Peru was upset by Bill Scanlon of Dallas, 6-3, 0-6, 6-0. Jeff Tarango of Manhattan Beach, Calif., defeated Tony Mmoh of Jamaica, 6-2, 3-0, Mmoh retiring with an elbow injury. Tarango will play fifth-seeded Johan Kriek next.

Brad Pearce of Provo, Utah, defeated Michael Robertson of Linwood, N.J., 6-3, 7-5, and will face top-seeded Ivan Lendl this afternoon on the stadium court. Jay Lapidus of Palm Beach Gardens, Fla., beat Mark Kratzmann of Australia, 5-7, 6-4, 6-2, and next meets fourth-seeded Brad Gilbert.

Second-seeded Boris Becker will play Richard Matuszewski, a first-round winner over Vince Van Patten, tonight at the stadium court.

In other matches, Marty Davis knocked off Gary Muller, 6-2, 6-0, and Brad Drewett defeated Ben Testerman, 7-6 (7-3), 7-6 (7-4). Last night, Simon Youl of Australia defeated Patrick Kuhnen of West Germany, 7-6 (9-7), 4-6, 6-3, and John Ross knocked off Al Parker, 6-3, 6-0.

Arias, the first player to advance to the round of 16, broke open a tight match with a break in the third game of the second set, getting to break point on a runaround forehand winner. Kures then double-faulted to give Arias a 2-1 lead.

Arias held his serve for 3-1, then broke again for 4-1 after taking Kures to deuce three times. Kures double-faulted again for an Arias advantage, then netted a forehand to fall behind, 4-1.

"I wasn't playing particularly well today," Arias said. "I didn't have any feel. So instead I just kind of pushed."

But Kures' big serve and forehand were off as well. "It was basically just a bad match," Kures said.

Kures, who defeated Christian Saceanu in three sets Monday, said fatigue got to him. "It hit me about 4-3 in the first set," he said. "It was downhill from there."

Scanlon, who played doubles later in the day with Lendl (defeating Robertson and Witsken, 6-4, 6-4), said of his second-set loss, "I just had a little concentration lapse. It happens when you get old."

Then, "I think {Yzaga} just fell apart. He just couldn't hit a ball in. I started the third set a little better. I attacked the net."

Witsken took control of his match in the opening set. He then began the second with a break in the second game. He reached advantage from deuce when Flach hit a smash long and took the game with a forehand passing shot with Flach at the net.

Witsken held serve at love in the third game, then broke again in game four. He got to 0-30 when Flach's crosscourt volley went long. At 30-all Flach netted a forehand volley and hit a forehand out for a 4-0 Witsken lead.