TORONTO - Goaltender Jonas Gustavsson had minor heart surgery, rookie right-winger Mikhail Stefanovich scored two goals in a scrimmage and returning forward John Mitchell continued to impress at Maple Leafs training camp Tuesday.

The NHL club's exhibition opener is at home Wednesday against Boston and coach Ron Wilson says among players in the lineup will be rookie standouts Tyler Bozak and Nazem Kadri, comeback longshot Jason Allison and intimidating bashers Colton Orr, Andre Deveaux, Phil Oreskovic and Jay Rosehill.

"We outlawed fisticuffs (during camp) so we've got some guys who are itching to show us what they can do if it comes to that," said Wilson. "We're good and ready for some exhibition games."

There'll also be games Thursday in London against Philadelphia, Friday in Pittsburgh and back home Saturday against the Flyers.

Gustavsson went to hospital with a racing heartbeat following fitness tests Saturday, took part in on-ice sessions Monday, and had minor surgery Tuesday.

"They go in and touch a part of his heart that was misfiring," said Wilson. "It's a simple procedure that's actually fairly common with athletes.

"It's not a difficult procedure. We don't expect him to miss more than 48 hours. You don't want him to put his gear on until he's comfortable and there's no risk of infection (at the site of the incision in the groin area)."

Gustavsson, who was lured from his Swedish team with a big free-agent deal, or Joey MacDonald, who got into 59 games with the New York Islanders last season, will probably start the NHL season as Vesa Toskala's backup.

"Joey MacDonald has looked really good in the scrimmages so he'll take up a couple of the periods (in exhibitions) Jonas would have played," said Wilson.

MacDonald spent six years in the Detroit organization before his stint with the Islanders.

"It's never been easy," said the 29-year-old goalie from Pictou, N.S. "When I started in Detroit there was Hasek, Osgood, all these big-name goalies, and when I came into this camp it wasn't any different than any other year.

"I had to battle it out last year to get the No. 2 spot and then the No. 2 turned into the No. 1. It's a strange game and things can happen in a hurry."

Stefanovich has been one of the best rookie forwards so far. After Toronto took him with its third pick in the 2008 entry draft, 98th overall, he scored 49 goals in 56 games with Patrick Roy's junior team in Quebec. He's from Belarus and speaks little English. He's 19 and, if he doesn't steal a big-league job, he can either be returned to Quebec or assigned to the AHL Marlies.

Allison would have to beat out Mitchell, Matt Stajan or Mikhail Grabovski to land the top-six forward spot he covets and that appears highly unlikely.

Wilson is especially high on Mitchell.

"He's in much better shape because he's had a year in the NHL under his belt," says Wilson. "He's comfortable out there and he's looked really good. He seems to be a little bit quicker. I'm hoping from big things from Mitchie. There's no reason that he shouldn't be able to score 20 goals in this league."

Mitchell paid his dues in the AHL before getting his shot with the Leafs, was initially used as a fourth-line mucker and was moved up after injuries and trades. He scored 12 goals in 76 games and sees himself skating as the third-line centre this season.

"That's a reasonable goal to reach," he said of Wilson's 20-goal expectation. "I'm going to go out there and work hard and try to get pucks to the net.

"It's a huge responsibility to play against the other teams' best lines and that's something I can definitely look forward to and I think I can handle that task."

Stajan is another returnee Wilson says has upped the physical ante.

"He seems stronger and he's skating much better," says Wilson. "He's worked hard this summer."

Players on the bubble include Jiri Tlusty, who spent most of last winter with the Marlies after starting with the Leafs.

"I'd like to see more out of him, to be perfectly honest with you, and that's why these exhibition games are huge for his career," says Wilson.

Oft-injured Mike Van Ryn, looking to earn a spot in the fifth-to-eighth defence slots after summer knee surgery, has been held out of scrimmages so far and will wait till next week for a shot at an exhibition outing.

"I have a soft spot in my heart for him for how hard and how well he played last year," said Wilson.

Said Van Ryn: "I can't wait to get going but we're easing into it."

The Leafs went without a captain last season and Wilson was asked if he's thinking about naming one before the start of the new season.

"No, I'm not," he replied. "This is a very important position and you just don't willy-nilly throw a C on somebody.

"This is somebody who is going to be here a long time and is worthy of carrying a letter like that. You don't have a captain just because everyone thinks you're supposed to have one. If we don't have a captain this year, I don't think it is a real negative."

It's too early in Luke Schenn's career to select the 19-year-old defenceman for the role, Wilson suggested."That's a potential candidate in the future but in this market I'm not going to burden a young kid," he said.

Oh, and about the muscle Wilson will flex against the Bruins: Orr was in 18 fights with the New York Rangers last season; Deveaux got into nine as a Leaf and six as a Marlie; Oreskovic was in three in the NHL and in 13 in the AHL; and Jay Rosehill, who'll also play Wednesday, piled up more penalty minutes -- 275 in the AHL -- than any other player in camp.