The 16-goal striker could be ruled out of Saints' promotion run-in after he was taken to hospital with an ankle injury during Saturday's 1-0 win over Bristol Rovers.
"Lee went over on his ankle and there is a concern there," said manager Nigel Adkins.
"Until we have the full diagnosis we don't have any information in that. But for Barney to be in as much pain as he was indicates that something quite significant was wrong."
Saints were already without midfielder Adam Lallana and winger Alex Chamberlain due to injuries on Saturday.
"Every club is going to have injuries across the course of the season, we have to deal with it," added Adkins.
Source: PA
Source: PA