The Nets would like to differ with the old saying that the best surprise is no surprise. The surprise of seeing Marcus Williams on the practice court yesterday was simply great.

Williams sprained his left wrist – yes, his shooting wrist – Tuesday and the outlook was grim. The start of the regular season was iffy for Williams. Vince Carter was taking a crash refresher course in Point Guard 101. Williams’ wrist was swollen to the size of a leg of lamb and he underwent the obligatory MRI. A light sprain, he was told. Out three weeks.

“It just swelled up right there on the spot and then I went home for a day and felt a lot better,” said Williams, who went through yesterday’s practice wearing a wrist brace. “I don’t know what it was. I started feeling better later that night and the next day [Wednesday], I really didn’t feel it.”

Said Carter: “Six weeks; forget six weeks. He healed in six hours.”

Williams claimed rest proved the major cure. He’ll sit tonight when the Nets play their first preseason home game, against the Sixers, and “maybe” will play next week. He insists he’ll be ready for the Nov. 1 season opener against Toronto. The only problem yesterday came later with expected soreness.

“I just had to get loose first and then during practice it wasn’t a problem. But right now, it’s kind of sore,” Williams said.

Sore, but cast-free. And maybe the Nets had a clue it wasn’t too bad. Williams said at first he didn’t even realize the injury was to his shooting side.

“When it first happened, I didn’t really even notice. As I was going to the doctor’s office I was thinking, ‘Damn, my left wrist,’ ” Williams recalled.

Williams’ absence put the Nets in a temporary bind. Eddie House, the third point guard, is on crutches after arthroscopic surgery on his left knee. So coach Lawrence Frank loved the surprise of seeing Williams on the court.

“We weren’t expecting to see him for a while. But the swelling went down. He got the thumbs up. I think it’s still real sore. But he went out there and gave a really, really good effort,” Frank said. “There’s no structural damage and the swelling has gone down. . . . We’re not going to play him [against Philadelphia]. There’s no rush. He just wanted to get his feet wet.”

Against Boston on Wednesday, Carter served as the backup to Jason Kidd.

“He looked pretty good, didn’t he? Vince is unbelievable,” Frank said. “He did a great job.”

Carter has played the point “sparingly” in his career.

“Now that Marcus is back, I guess that was my hello and goodbye,” Carter said. “It’s always something I wanted to do. I played a little point last year, even with Jay in there, giving him the opportunity to play off the ball. I felt comfortable, knowing the offense and being around it a little bit really helps.”