Ospreys scored a dramatic late try to beat Premiership champions Leicester Tigers and reach the last 16 of the Heineken Champions Cup.

Owen Williams kicked the winning conversion to prevent hosts Leicester, who had already secured qualification, ending with a 100% winning record.

Leicester led on four occasions but in the end fell to defeat at Welford Road.

Ospreys would have gone through with a losing bonus point, but the Welsh side's last-gasp victory keeps them in with a chance of a home tie when the Champions Cup returns at the end of March.

They won despite losing two players to first-half injuries, and the sight of Wales international hooker Dewi Lake limping off will particularly worry national coach Warren Gatland, with their Six Nations opener at home to Ireland just over two weeks away.

Lake had given the visitors an ideal start by touching down after a driving maul from a lineout.

The Tigers' response was quick and almost identical, but while Ospreys managed to halt Leicester's drive for the line, they were powerless to prevent Jack van Poortvliet darting over from close range.

Ospreys could have found themselves 10 points down half-time but instead went into the interval level, keeping Leicester out after a sustained spell of pressure from the home side, before forcing a penalty which Williams kicked to make it 13-13.

Another attacking lineout was the platform for Harry Simmons' try, his second in consecutive Champions Cup matches for Leicester after scoring in the win at Clermont which secured Tigers' qualification with a game to spare.

Back came Ospreys though, with a loose Leicester pass kicked clear for the onrushing Keelan Giles to collect and run in unchallenged from the halfway line.

South African World Cup-winner Handre Pollard's third and fourth penalties of the evening looked to have put Leicester on course for victory, stretching the hosts' lead to six points as time ticked away.

But Ospreys fought back once more and while video replays confirmed Keiran Williams had grounded his effort short of the try line, their persistence paid off when Morgan went over and the try was awarded almost 12 minutes after the allotted 80 had been completed.

Line-ups

Leicester Tigers: Steward, Potter, Scott, Kelly, Simmons, Pollard, Van Poortvliet; Whitcombe, Clare, Cole, Chessum, Henderson, Liebenberg (c), Reffell, Cracknell.

Replacements: Montoya, Richardson, Hurd, Wells, Jansen, Youngs, Gopperth, Atkinson.

Ospreys: Evans, Cuthbert, Collins, Hawkins, Giles, O Williams, Morgan-Williams; Smith, Lake, Botha, Beard, Jones, Davies, Tipuric (c), Morgan.

Replacements: Baldwin, Thomas, Henry, Sutton, Morris, Aubrey, K Williams, North.

Referee: Tual Trainini (France)