Ireland captain Rory Best will miss his province Ulster's first two European Champions Cup matches because of a hamstring injury the club announced on Monday.

The 35-year-old veteran -- who skippered the British and Irish Lions midweek team on their successful tour of New Zealand earlier this year -- suffered the injury in training last week.

However, the extent of the damage did not surface until Monday.

"Following a scan, it has been confirmed that Rory Best has a hamstring tear and will be out of action for approximately four to six weeks," Ulster said in a statement.

Ulster open their Champions Cup campaign against English giants Wasps in Belfast on October 13, then travel to French outfit La Rochelle nine days later.

Ireland's opening Test of their autumn series is against South Africa on November 11, followed by clashes with Fiji and Argentina, who knocked the Irish out of the 2015 World Cup at the quarter-final stage.

source: AFP