Ireland were given an injury scare ahead of the Six Nations after Johnny Sexton was replaced 10 minutes into Leinster's Champions Cup clash with Wasps due to concussion.
Leinster captain Sexton received treatment after being dazed but, as the game continued around him, he got back to his feet and produced a tackle.
However, once play stopped, Leinster's medic returned to the field and the fly-half was helped from the pitch.
Ireland face Wales in their Six Nations opener at the Aviva Stadium on February 7 and coach Joe Schmidt will hope to have a fully-fit Sexton at his disposal.
"Johnny got just a head knock. We didn't want to risk him going back out there," Leinster head coach Leo Cullen said.
"He's up and about in the dressing room being assessed, so he'll follow the usual return to play protocols.
"Those guys are in (Ireland) camp next week, but he looked OK in the dressing room there."