Alex Mitchell faces a race against time to be fit for England's Nations Championship opener against South Africa in Johannesburg after suffering a hamstring injury during a squad training camp last week.
Northampton director of rugby Phil Dowson confirmed on Wednesday that Mitchell is unlikely to feature again in the Premiership this season — even if the league leaders reach the June 20 Twickenham final — making his availability for England's summer tests highly uncertain.
England's Nations Championship programme opens against the Springboks in Johannesburg on July 5, followed by Fiji in Liverpool and Argentina in Buenos Aires. Steve Borthwick could now be without his Lions-selected scrumhalf for all three matches.
"He's pulled it and he's done a decent job on it," Dowson said. "It's going to be a push to get him any rugby for us for the rest of the season."
The timing is particularly cruel for Mitchell, who also missed the final two rounds of this year's Six Nations after tearing the other hamstring.