DENVER -- Paul Tracy is unbeaten on street circuits this season and Bruno Junqueira has led every lap ever run by a Champ Car around the Pepsi Center.

One of those trends will go by the boards in Sunday's Grand Prix of Denver as Tracy tries to move further ahead of Junqueira and get a firmer grip on his initial CART championship.

The 34-year-old Canadian owns a 28-point lead over the 26-year-old Brazilian going into the 15th of 19 races this season. Tracy has amassed 192 points and has a career-high six victories, including winning street shows at St. Petersburg, Long Beach, Toronto and Vancouver.

"We still have our work cut out for us and it's not just a two-man battle between me and Bruno because Michel (Jourdain) is right back in this deal," said Tracy, who finished sixth last weekend at Montreal while Jourdain triumphed.

"Bruno was awfully tough last year at Denver but street courses have been one of our strengths this season for Team Player's."

	Paul Tracy has been a blur on street circuits.

Junquiera is coming off a forgettable performance where he spun twice and finished 13th -- his second straight race without a point.

"We've got to forget about what happened the last two races and get a victory," he said. "I started on the pole and led every lap here last year so I feel good about our chances.

"This year has been between Paul and myself and I need to win this race."

The high altitude and tight course put a premium on handling in 2002.

"It's not so much a case of the drivers adapting to the thin air, because we have a number of races that are a test of stamina and physical conditioning," said Tracy. "It's probably even tougher from a car aerodynamics standpoint because the thin air affects such things as grip and braking.

"Denver is slick and has transitions from asphalt to concrete so it definitely presents some challenges."

Junqueira, who along with teammate Sebastien Bourdais is giving owners Paul Newman and Carl Haas their 350th CART start, agreed with his rival.

"It's a very, very difficult track because you are racing at a high altitude and you lose a lot of downforce on the car. Then the car is light -- much more than you are used to and you have to be really competitive to keep the car on track and run fast laps."

Jourdain's second win of 2003 came at the expense of Alex Tagliani, who dominated the race but wound up fourth because of faulty fuel strategy and a late caution flag. But the 26-year-old native of Mexico City had Long Beach won before a mechanical disaster on his final pit stop robbed him of victory.

"I feel for Alex because he deserved to win but I know how he feels," said Jourdain, who trails Tracy by 35 points. "We've got a little momentum and I've had a fast car on the street circuits this year. It won't be easy to catch Paul but we've still got a shot."

There will also be a pair of debuts this weekend.

Because of all the complaints about blocking on street courses, CART is instituting one-lap qualifying (like Formula One) for Denver and Miami instead of the 15-lap sessions where everyone runs together.

"It's good news as far as I'm concerned," said Tracy, who has had fingers pointed at him (and given to him) all season for blocking other drivers. "There aren't going to be any complaints about being blocked or running out of time to get a really good fast lap.

"You just have to put all your focus into squeezing every tenth you can out of the car."

F1 veteran Mika Salo is making his CART debut and replacing Max Papis for PK Racing in a move that was supposed to happen at Montreal. The 36-year-old native of Finland has been hanging with PK Racing all season and recently had an impressive test at Mid-Ohio.

"I'm not ready to quit open wheel cars and I've been hoping for this opportunity all season," said Salo, who drove for Toyota before being bumped for 2002 CART champion Cristiano da Matta.

Robin Miller covers open wheel racing for ESPN and ESPN.com