STAR North Melbourne forward Drew Petrie had to undergo a fitness test on Saturday morning, only hours before his excellent five-goal performance in the Kangaroos' win over the Western Bulldogs. ??

Petrie, whose haul pushed him into the lead of the Coleman Medal race with 52 goals, felt sick on Wednesday night ahead of the clash. At first the club wasn't worried, thinking the 29-year-old would have enough time to recover.

Even at training on Friday, coach Brad Scott thought Petrie would be fine, "but he took a turn for the worst" on Friday night.

"[He] was pretty sick last night. If the game had been yesterday he wouldn't have played," Scott said after his team's 54-point win. ?

Petrie did a fitness test at the club's home ground, was passed fit to play, and was one of many strong contributors in the win.

"[It was] a fantastic effort for Drew to step up," Scott said. "To get up and play was fantastic and he led from the front."??

Making the effort more impressive was the fact Petrie was paired against Bulldogs defender Brian Lake. Lake outplayed Petrie the last time the sides met - in the Bulldogs' round-seven win - and Petrie responded to the challenge.??

His bag of goals was made up of three in the first half and two in the second, and he also limited Lake's offensive streak.

Petrie's long-time teammate Brent Harvey noticed the Coleman Medal leaderboard flash up on the scoreboard late in the last quarter and was pleased with what he saw.??

"It's fantastic, really," Harvey told AFL.com.au.??

"He's still got four games to go so if he ends up on top it'd be great for our football club and great for Drew.??

"But if he doesn't, I don't think Drew plays for the individual awards. His goal is to get us into the finals and he's doing an exceptional at the minute."??

Petrie has kicked 23 goals in his past four games and Harvey, who was at the club when Petrie played his first game in 2001, said the key forward was in career-best form.

Petrie is capable of the spectacular, grabbing a big mark or kicking an extraordinary goal. But Harvey put his success down to one thing perhaps less appealing.  ?

"He's just a competitor. He's one of the hardest trainers at the club if not the hardest," Harvey said.

"He does the most goalkicking, he does the hardest weights. I think he's got a little bit of OCD (obsessive compulsive disorder) in him but that's probably a good thing. ??

"He leaves nothing to chance, and it's coming back ten fold for him." ??

Callum Twomey is a reporter for the AFL website. Follow him on Twitter at @AFL_CalTwomey.