Leinster are optimistic regarding a return to play for Caelan Doris sooner rather than later. 

The number-8 hasn't played since withdrawing from the Ireland squad ahead of their opening Six Nations game with Wales.

Doris had complained of symptoms associated with concussion.

He's since believed to have seen a neurologist in Birmingham to have the issued adequately dealt with.

Doris had been pictured on the training pitch for Leinster in recent days, sparking hopes of an imminent comeback.

"He's doing a progressive return to contact," Leinster coach Stuart Lancaster revealed on Monday, "So he's been doing non-contact training, in and out of sessions, just to build up confidence, I guess.

"Yeah, he's on the road to recovery, and I think we're hopeful that he'll get back playing again soon."

When pressed on when "soon" might be, Lancaster replied it would be "within the next month".

The senior coach refused to commit Doris to returning in time for the Pro 14 final with Munster, adding, "A lot depends.... it's a progressive return-to-play on the back of a concussion.

"It depends on the reaction, but it's certainly making moves in the right direction, and physically he's in great shape.

"So yeah, we're optimistic."

Lancaster also sounded a positive not on the fitness of Adam Byrne.

The flying winger had appeared poised for a return to provincial action last month, after more than a year out with a hamstring injury.

Byrne then sustained a quad problem while in the final stages of his rehab process.

Lancaster told a press conference, "I feel sorry for Adam, because he's worked so hard - he's so diligent in his rehab.

"So to come back close to returning to play, and then have a setback in a different area... He'll be back towards the end of the season which is great really for him, because you couldn't meet anyone more diligent."

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