Match ends, Heart of Midlothian 3, St. Johnstone 0.
Kyle Lafferty scored twice in a decisive display as Hearts reached the Scottish Cup quarter-finals with a comfortable win over St Johnstone
Lafferty drilled home a precise left-foot shot from Arnaud Djoum's pass to put the hosts into an early lead.
Scott Tanser came closest for Saints before Ross Callahan volleyed wide.
Demetri Mitchell's sweet 20-yarder into the top corner put Hearts in command and Lafferty slid home Michael Smith's cross to put the outcome beyond doubt.
Connor Randall might have added a fourth but his effort was cleared off the line.
Hearts will discover their quarter-final opponents on Sunday, with the ties to be played on the weekend of 3-4 March.
The visitors were looking to avenge their narrow defeat at Tynecastle in the Premiership a week ago and began promisingly with Richard Foster and Scott Tanser on the flanks causing the home defence problems.
But the Perth side were victims of their own undoing when they gifted Hearts the opener after just eight minutes.
Saints were awarded a throw-in on the halfway line and rather than go down the line, Joe Shaughnessy threw the ball into the midfield.
Djoum nipped in to steal the ball from Murray Davidson and play in Lafferty, who took one touch before angling his shot beyond the outstretched arms of Alan Mannus in the St Johnstone goal.
It was Lafferty's 13th goal for the club after joining in the summer from Norwich City.
Saints boss Tommy Wright though was visibly furious with his players, and it proved to be a short afternoon for Chris Millar when he was replaced after only 26 minutes, striker Denny Johnstone coming on.
Hearts though have been almost inpenetrable at the back, with the trio of John Souttar, Christophe Berra and Aaron Hughes forming an impressive barricade.
David Wotherspoon, who was sent off last week, used his pace to get get away from Mitchell. He managed to play in Chris Kane, but Hearts keeper Jon McLaughlin was up to the task.
Hearts came out the traps quickly in the second half and Lafferty did well to knock the ball down to Callachan, who made a tremendous run from midfield. He turned on the edge of the box but his right-foot volley drifted just wide.
The home side duly doubled their advantage in some style after 54 minutes.
Djoum broke away down the right and played the ball across field where he found Mitchell. The left-back, on loan from Manchester United, showed tremendous skill and vision to control the ball with his first touch and rifle it high into the top-right hand corner
Lafferty put the tie to bed before the hour mark with a superb third goal.
The Northern Irish striker, watched by national manager Michael O'Neill, controlled the ball 30 yards out and played the ball wide to Michael Smith. He knocked it straight back across the six-yard box where Lafferty continued his run and fired home left-footed from close range.
Hearts were growing in confidence with Djoum and Callachan in particular beginning to boss the midfield area.
Saints chances were few and far between and Wotherspoon will be disappointed there were no takers when he found space down the right, but his cross into the box was cleared away by Souttar.
Hearts continued to pile on the pressure and substitute Randall had an effort cleared off the line by Jason Kerr as the Saints defence withered.
When Hearts last won the cup in 2012, they knocked out St Johnstone on their way to the final. Few inside the crowd of 12,393 would bet against the Tynecastle side making their way back to Hampden.
Hearts boss Craig Levein: "We got a good goal which settled us but it wasn't until the second goal that we started to dominate the match.
"Kyle's first goal was a really difficult finish but he does that regularly. He got two today and had a really good performance.
"We looked more potent today and I thought the goals were excellent.
"Young Demi's goal was wonderful and he's shown real quality since he came here. He has really added to the group.
"I would love to get another home tie because I feel this is becoming like the Tynecastle of old where teams don't like to visit."
Saints boss Tommy Wright: "Same old story. We started the game quite well and got into good positions. Then we give away an absolutely horrendous goal.
"It is not an area you want to throw the ball into - it was a poor, poor decision and it cost us a goal. There were too many mistakes, too many individual errors and it has happened too often.
"Hearts have played well, but Alan Mannus has not had much to do.
"We prepare them, but at certain times in games they are making calamitous mistakes, and they are leading to goals. They have got to make better decisions all over the park.
"The one thing you can say is that we can concentrate on the league now."
- 66AdaoBooked at 15minsSubstituted forBuabenat 60'minutes
- 24MitchellSubstituted forRandallat 77'minutes
- 9LaffertyBooked at 72minsSubstituted forHendersonat 84'minutes
- 8DavidsonBooked at 75mins
- 7MillarSubstituted forJohnstoneat 26'minutes
- 28WillockSubstituted forAlstonat 61'minutesBooked at 67mins
- 10WotherspoonBooked at 30mins
- 25KaneBooked at 88mins
- Kevin Clancy
- Shots on Target
Second Half ends, Heart of Midlothian 3, St. Johnstone 0.
Delay over. They are ready to continue.
Delay in match Steven Anderson (St. Johnstone) because of an injury.
Foul by Christophe Berra (Heart of Midlothian).
Christopher Kane (St. Johnstone) wins a free kick in the defensive half.
Christophe Berra (Heart of Midlothian) wins a free kick in the defensive half.
Foul by Christopher Kane (St. Johnstone).
Christopher Kane (St. Johnstone) is shown the yellow card for a bad foul.
Aaron Hughes (Heart of Midlothian) wins a free kick in the defensive half.
Foul by Christopher Kane (St. Johnstone).
Foul by Prince Buaben (Heart of Midlothian).
David Wotherspoon (St. Johnstone) wins a free kick in the defensive half.
Substitution, Heart of Midlothian. Euan Henderson replaces Kyle Lafferty.
Foul by Ross Callachan (Heart of Midlothian).
Steven Anderson (St. Johnstone) wins a free kick in the defensive half.
Attempt saved. Michael Smith (Heart of Midlothian) right footed shot from the centre of the box is saved in the centre of the goal.
Attempt saved. Connor Randall (Heart of Midlothian) right footed shot from the centre of the box is saved in the centre of the goal.
Substitution, Heart of Midlothian. Connor Randall replaces Demetri Mitchell because of an injury.
Foul by Demetri Mitchell (Heart of Midlothian).