Tonga's Alisona Taumalolo (L) tackles Canada captain Pat Riordan during their Rugby World Cup Pool A match at Northland Events Centre in Whangarei, Sept 14, 2011. [Photo/Agencies]

WHANGAREI, New Zealand - Winger Phil Mackenzie scored a late try for Canada to help his side fight back from a seven-point, second-half deficit to open their rugby World Cup campaign with a 25-20 victory over Tonga on Wednesday.

Lock Jebb Sinclair scored a first half try for the Canadians while number eight Aaron Carpenter barged over after his side had gone 20-13 down with about 20 minutes remaining. James Pritchard added two penalties and two conversions for the North Americans in the Pool A clash.

Centre Siale Piutau scored two tries while fullback Kurt Morath added 10 points for the Tongans, who have now lost all three of their World Cup clashes with Canada.

Piutau scored his first try after 19 phases late in the first half that reduced the deficit to 10-7 at the break then scored another midway through the second half to give his side their seven-point advantage before Carpenter and Mackenzie struck back.

Tonga's Thomas Palu (R) fumbles a high ball during their Rugby World Cup Pool A match against Canada at Northland Events Centre in Whangarei, Sept 14, 2011. [Photo/Agencies]