Stilian Petrov shattered Hearts for the second time in three weeks at Tynecastle with a double as Celtic cruised into the quarter-finals of the Tennents Scottish Cup.

Henrik Larsson's last-gasp goal and late sendings-off of Paul Hartley and Alan Maybury compounded Hearts' misery.

Petrov took the plaudits with a brilliant brace to take his impressive tally to six in seven games.

Celtic striker John Hartson missed the game with a back injury and was replaced by Alan Thompson with Chris Sutton moving up front to partner Larsson.

And it was that pairing which combined to give Celtic the perfect start with Petrov's third-minute lead.

Sutton played the ball up to Larsson and he turned and put in the overlapping midfielder.

Petrov coolly poked the ball over the advancing Craig Gordon from close range.

The goal further fired up the Hearts crowd, who were already baying for the blood of Celtic and chief executive Chris Robinson holding aloft sheets of paper with 'Robinson Must Go'.

But the players struggled to get going and another lapse allowed Larsson to pull the ball back for Sutton, whose right-foot drive was pushed over the crossbar by Gordon.

The Hearts keeper was fortunate in the 15th minute when Sutton chased down a long ball and seemed to be taken out by him.

Andy Webster was frustrating the visitors with a number of full-bloodied challenges.

His team-mates did eventually put together a promising move on the half-hour but Hartley's right-foot shot was easily saved low by a rejuvenated number one Robert Douglas.

But the writing was on the wall for the home side and they fell further behind in the 33rd minute with the same combination working again to ruthless effect.

Larsson flicked on Sutton's pass, with the Hearts defence again getting drawn to the ball, and Petrov drilled an unstoppable right-foot effort first time high into the top corner.

Phil Stamp lost his patience and floored Neil Lennon soon after and the Celtic man's reaction earned the pair a place in referee Willie Young's book.

Hartley followed them swiftly with Lennon again the target of some rough treatment from the home side.

Stamp tried to lift the home crowd again but he fired his free-kick past the post before Gordon comfortably saved Sutton's strike after another good build-up by Celtic.

Just three minutes into the second half, Hearts manager Craig Levein made a double substitution, bringing on Kevin McKenna and Robbie Neilson for Robert Sloan and Neil MacFarlane.

Mark de Vries could have pulled the home side back into the tie when he was found by Stamp in the box but he blazed his right-foot shot just past Douglas' upright from nine yards.

Levein made a last-ditch attempt to resurrect their cup hopes by throwing on Andy Kirk for Patrick Kisnorbo in the 70th minute.

But the home side's hopes were dashed as soon as Hartley was shown his second yellow card for a foul on Lennon and an outburst at Young in the 85th minute.

Petrov could have sealed his hat-trick late on but he fired over with just Gordon to beat and Sutton shot at Gordon.

Maybury became the second Hearts man to be sent off for a late challenge on Lennon in injury time.

There was still time for Larsson to head home in the dying seconds after Gordon had pushed away Petrov's drive.

But nothing could deny Petrov his glory or Celtic becoming the first side in the last eight of the competition.

Teams

Hearts Gordon, Maybury, Pressley, Webster, Stamp, de Vries, MacFarlane (Neilson 50), Wyness, Hartley, Kisnorbo (Kirk 71), Sloan (McKenna 49).

Subs Not Used: Moilanen, Weir.

Sent Off: Hartley (85), Maybury (90).

Booked: Stamp, Hartley, Maybury.

Celtic Douglas, McNamara, Varga, Sutton, Thompson, Pearson, Agathe, Lennon, Petrov, Kennedy, Larsson.

Subs Not Used: Marshall, Valgaeren, Lambert, Maloney, Beattie.

Booked: Lennon, Sutton.

Goals: Petrov 3, 33, Larsson 90.

Att: 15,372

Ref: W Young (Scotland).