Republic of Ireland boss Martin O'Neill has cast doubt over two of his key players ahead of Euro2016.

Norwich City winger Robbie Brady sat out Monday's training session with a back spasm and now faces a race against time for their Group E opener against Sweden on June 13.

Brady, who can also operate at left-back, is an important member of O'Neill's side and the manager is hopeful he can shake off the issue soon and avoid missing the match in Saint-Denis in a week's time.

"Hopefully not, he has definitely improved since the spasm occurred so that is good news, so I think things are not too bad," O'Neill told Sky Sports.

Also recovering from injury is captain and all-time leading scorer Robbie Keane, who has a thigh issue, but is keen to prove his fitness for Sweden.

O'Neill did not give much away when quizzed on the LA Galaxy star's chances of taking on the Swedes.

"That I couldn't tell you at the moment, but he is genuinely improving," he added.