Star Kangaroos forward Ben Brown has suffered a calf injury at training on Thursday, according to The Herald Sun.
The big man left the track early in discomfort in the hands of club medicos and will undergo scans to determine the severity of the issue.
It could place Brown in doubt for North Melbourne's round one clash against St Kilda in what would be a major blow, especially given a number of his teammates are currently sidelined.
Skipper Jack Ziebell (calf) has missed a large chunk of the pre-season, Jared Polec (foot) is being managed and Robbie Tarrant (foot) had a recent setback.
Brown has been one of the league's most durable players in recent years, playing 22 games in each of the last five seasons.
The 27-year old is coming off a career-best 64-goal campaign where he finished runner-up in the Coleman Medal.
