England captain Dylan Hartley is back in full training for the first time since being knocked unconscious during the Grand Slam decider against France in March.
The hooker is in line to feature for Northampton against Gloucester in the Premiership on Saturday.
"He's done a full week and has been going through the return-to-play protocols," said coach Alan Dickens.
"He's bouncing around the place and back to his usual self."
If 30-year-old Hartley does return from the replacements bench, it will be a significant boost for England before the summer tour to Australia.
England boss Eddie Jones says Hartley will lead the side down under if he proves his fitness for the three-Test series.
Meanwhile, Hartley has been seeking advice over his recovery from his club team-mate George North. The Wales wing took a period away from the game in 2015 because of his own concussion problems.
"Dylan has been around the house a few times for a few coffees and a few chats," North told BBC Radio 5 live. "Anyone who has had concussion, or a number of concussions back-to-back, can really sympathise.
"People don't see a cast on his head or strapping around his brain - it's not like an injury where you have a physical issue like a limp - so it's very difficult to come to terms with.
"You only have one head so make sure you take care of it. If it takes you two or three weeks longer [to recover] then take your time. There is no point rushing it."
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