David Hearn will defend a two-shot lead in the final round of the RBC Canadian Open as he seeks to become the first Canadian winner of the tournament in 61 years.

The Ontario-born 36-year-old started the day three shots behind overnight leader Chad Campbell but a four-under-par 68 saw him climb to the top of the leaderboard.

It might have been even better for Hearn as he chases his maiden PGA Tour crown, but he bogeyed the par-four 17th having picked up birdies on the previous two holes at Glen Abbey Golf Course.

Two-time Masters winner Bubba Watson and Jason Day - who tied for fourth at the Open Championship on Monday - are Hearn's nearest challengers on 13 under after rounds of 68 and 69, respectively.

Michael Putnam (68) and Brooks Koepka (68) are a further shot back on 12 under while Campbell is in a group of five players on 11 under after only managing a 75, which included a triple-bogey seven on the 11th.

Canada have not been able to celebrate a home winner in the event since 1954 when Pat Fletcher lifted the title in Vancouver.