England hooker Dylan Hartley is struggling to be fit for Northampton's Amlin Challenge Cup final clash with Bath in Cardiff on Friday night.
Saints rugby director Jim Mallinder revealed the Hartley is yet to take any contact in training as he fights to shrug off a shoulder injury he suffered against Leicester in March.
The hooker is expected to be fit for England's three-Test June tour to New Zealand, but is under pressure to face Bath and then play against Saracens in the Aviva Premiership final at Twickenham on May 31.
Mallinder said: "Hopefully Dylan will be back, we're not too sure, he's improving by the day, but he's got to be fit to play, and our other hookers are playing well.
"It's a strength thing with Dylan now, I think in overall terms his shoulder has improved, he's out there doing running all the time.
"The physios are constantly doing tests on him, comparing it to the other arm, to see where that is.
"It's got to reach a certain level before they're happy for him to take contact.
"He still hasn't taken contact yet."
Northampton could also be forced to do without prop Salesi Ma'afu at Twickenhan after the Australian was sent off for punching Tom Youngs in Friday's victory over Leicester.
The Tigers had Dan Bowden, Youngs and Vereniki Goneva sin-binned in an ill-tempered affair, leaving Mallinder hopeful the officials will appreciate the derby intensity.
"He didn't start it, and that's not an excuse, but hopefully the whole game will be taken into consideration," said Mallinder.
"Hopefully he won't face a ban, but that's what we've got to cater for, you never know who will be injured or sent off, we've got a strong squad and we'll trust in it as always."
Mallinder backed Saints to handle the pressure of two successive finals, after rotating his squad in the latter stages of the regular season in preparations.
British and Irish Lions prop Alex Corbisiero is back after long-term knee trouble, and Mallinder expects him to play a key role as Saints chase silverware.
"We've rotated the squad over the last five weeks or so to make sure no one has played week to week, with this potential run of matches in mind," said Mallinder.
"So now we're here I think we're very well prepared for that, and that all our players will be fresh.
"Hopefully that allows us to go full-tilt at both games, and it's going to be an exciting couple of weeks.
"It's good to see Corbisiero back, that's his second game back, he's getting a bit of game time and so hopefully he can have two very big weeks now."