Some of Warren Gatland's British & Irish Lions squad are in a race against time to be fit for the tour of South Africa.
#1. Dan Biggar (England)
Saints lost fly-half Biggar to concussion during the first half of the game against Gloucester last weekend.
The Wales star was involved in an unfortunate collision with Billy Twelvetrees and later failed a head injury assessment.
Chris Boyd said: "He's okay. He had that clash with Billy Twelvetrees and failed his HIA. He didn't seem to have any symptoms.
"We've got a bit of a longer week, not playing until next Monday (at Newcastle) so he's got plenty of time to hopefully recover."
#2. Chris Harris (Scotland)
The centre has revealed he is set to be fit to go head-to-head with Semi Radradra against Bristol Bears on Monday night.
The 30-year-old missed Gloucester’s 31-7 victory over Northampton Saints last weekend with a shoulder injury
Harris said: “I should be good to go this week. I will just do a little bit of contact [in training] to see how that is and if it is not right I think it would be stupid to force it, but I will just see how it goes this week.
“It is a Monday night game so we are not in until Wednesday anyway so it is still a good amount of time [to fully recover].”
#3. Jack Conan (Ireland)
The number 8 lasted just 24 minutes of his side’s Rainbow Cup encounter with Irish provincial rivals Connacht.
Fresh from being named in Warren Gatland's 37-man squad for the tour of South Africa, Conan took a knock carrying the ball up the pitch and colliding with Connacht No.8 Jarrad Butler.
He will follow the Graduated Return to Play Protocols this week
#4. Courtney Lawes (England)
Lawes’ Six Nations was cut short by a pectoral injury in March, but the hard-hitting forward has revealed he is closing in on a comeback.
“I’m only a couple of weeks away from being fit now, two or three weeks, so I’ll get a bit of game time before the end of the season, which is great,” said Lawes.