Mario Lemieux's bone infection is "much improved," but the Pittsburgh Penguins' all-star center cannot resume exercising until next month, his doctor said yesterday.

After undergoing surgery last July to partially remove a herniated disk, Lemieux developed an infection in his lower back that spread to the bone. The infection can cause crippling, debilitating pain, but was detected in its early stages, when it often can be cured without complications, according to Dr. Charles Burke.

"The infection is under control," said Burke, one of the Penguins' team physicians.

Lemieux, who has been taking antibiotics to combat the infection, needs another month of recuperation before he can begin exercising, Burke said. The Penguins hope he can begin light skating next month and resume playing in January.

Canadiens Deal Hayward

Unhappy goaltender Brian Hayward got his wish yesterday when the Montreal Canadiens traded him to the Minnesota North Stars for 21-year-old defenseman Jayson More.

Hayward, 30, walked out on the Canadiens Oct. 8 to press his demand for a trade and was suspended without pay. He was put back on the payroll a week later, but his request to rejoin the Canadiens was turned down by General Manager Serge Savard.

Hayward has been training with the McGill University team for the last three weeks.

More was drafted 10th overall in 1987 by the New York Rangers and traded to Minnesota on Nov. 1, 1989, for Dave Archibald, who was picked sixth overall in the same draft. More is to report to Montreal's American Hockey League club in Fredericton.

Less Bloom on Cheek

There will be no "thirtysomething" rookie of the year this season, as there was in 1989-90 when the now 32-year-old Sergei Makarov won the award. But this year's list of likely candidates for the Calder Meorial Trophy includes players from several countries, with a variety of backgrounds and ages.

Chicago's Ed Belfour, the New York Rangers' Mike Richter, Detroit's Sergei Fedorov, Los Angeles's Rob Blake, Pittsburgh's Jaromir Jagr and Quebec's Mats Sundin are all in the mix.

A new rule says that to be eligible for the Calder a player must not have turned 26 by Sept. 15 of the season in question. The old rules concerning games played still apply: No more than 25 games in any one previous season nor six or more games in any two preceding seasons.

Fedorov, a center who left the Soviet Union this summer, is the leading scorer among rookies and is helping the Red Wings' resurgence. But Blake, a defenseman formerly of Bowling Green, is right behind him in scoring and is a good part of the reason why the Kings are a point out of first place in the Smythe Division.

Belfour and Richter are goalies who are familiar names because both played 23 regular season games before this season. Belfour, who leads all goalies with nine wins, is one of the oldest rookies, and the Blackhawks might still be playing when he turns 26 on April 21, 1991. Jagr, on the other hand, won't be 19 until Feb. 15.

Whatever He Wants

As George Orwell suggested in "Animal Farm," some people are more equal than others. When you are a defenseman about to turn 30 and your name is on most of the recent Norris trophies (for the league's best defenseman), you get a little more latitude.

The Boston Bruins practiced Tuesday for their first meeting with arch-rival Montreal on Wednesday, but star Ray Bourque had the day off. No, it wasn't because of the shoulder injury he has recently recovered from, but "because he had to get a haircut," Coach Mike Milbury told the Boston Globe. . . .

Jari Kurri has 13 goals and 24 points in eight games for the Milan Devils of the Italian league. Fellow former Edmonton Oiler Mark Napier is playing in Varese.