Jim Mallinder has confirmed that Tom Collins pulled his hamstring in Saints’ defeat to Exeter at Franklin’s Gardens on Friday night.
Collins was forced off inside the first two minutes after bravely denying Chiefs wing Jack Nowell at the last.
The 20-year-old was replaced by Kiwi utility man James Wilson as the home side went on to suffer a 24-18 Aviva Premiership loss.
And Collins now looks set for a spell on the sidelines after Mallinder revealed the nature of the problem.
“Tom’s pulled his hamstring,” said the Saints boss.
“It was disappointing to lose him so early on, but I thought James came on and did well.”