Jon Fisher says that new signing Luke Eves has been the top trainer at Saints this summer.
Eves was signed on a short-term deal in June as Saints sought to add cover to their squad during the World Cup.
And Fisher, who was handed a deal at Franklin’s Gardens after a successful trial during pre-season last year, has been impressed with the former Bristol centre.
“The new lads are brilliant,” Fisher said.
“Guys come in and they try to raise the bar in training, which is what I tried to do last year.
“In particular, Luke Eves, who has come in on a six-month deal. For me, he’s been the performer of the summer in the fitness games out there.
“He’s really, really superb and that’s great to see.”
Eves ended his second spell with Bristol in May after they lost the Championship play-off final to Worcester.
The 26-year-old played for England in the 2009 World Under-20 Championship final and will be looking to secure a long-term deal at Saints this season.