A 57th minute winner from Graham Cummins, his first league goal of the season, was enough to win the points at home to Hearts in the Scottish Premiership.
Zander Clark, the man of the match, had an outstanding game and was crucial in preserving Saints' unbeaten home record against the visitors who have not won at McDiarmid Park in the league since 2012.
The players, when celebrating what proved to be the matchwinner, held up Dave Mackay's number two shirt in recognition of the club captain who announced his retirement from playing on Thursday morning.
Next up for St. Johnstone is the Betfred League Cup quarter-final at Aberdeen on Thursday night.
Saints headed into Saturday’s clash with Hearts on the back of a fine 2-0 win away to Partick Thistle, but entered the match without Danny Swanson, Chris Millar or the recently retired Dave MacKay.
Hearts kicked off shooting into the Ormond Stand, and it was the visitors who fashioned the first chance of the game, as Watt broke quickly before feeding Nicholson who blasted straight at Clark on three minutes.
It was then Johnsesn who came close from a counter attack, fumbling from inside the six yard box before Clark gathered.
Ricky Foster then pulled off block of the season, heading a Watt acrobatic effort off the line, not that the former Aberdeen defender would have known much about it. Saints were matching Hearts like for like in the early stages.
It was then Zander Clark’s time to shine, as Nicholson weaved his way into the box to set up Johnsen, but the superb stopper saved sublimely from 12 yards.
Clark again denied Hearts from close range, as Jamie Walker fdound space but the keeper blocked his thunderbolt with one hand to keep the scores level.
On 27 minutes, MacLean and Davidson linked up well and the latter strode into the box, but caught his shot late and it was held comfortably by Hamilton.
A quick counter attack with fluent one touch play between Craig, MacLean and Coulson ended with Cummins trying an acrobatic effort which was saved as Saints were beginning to come into the game offensively.
But the break came with the game goalless, with Tommy Wright’s side looking to build on their form from the latter stages of the first half. Half time: St Johnstone 0-0 Hearts.
Saints started the second half strongly, but Hearts were keen to open the scoring and standout Clark saved Watt’s free kick from 20 yards with aplomb.
Clark again rescued Saints after 55 minutes, tipping a Rossi header over the bar from a corner.
But it was Saints who took the lead, as Liam Craig smashed a shot at goal for Graham Cummins to tap in as Hamilton has committed. The two wheeled away to produce a shirt with “#2 MacKay” on the back in an excellent tribute to the recently retired skipper. 1-0.
Saints first switch was to replace Coulson with Wotherspoon, after the Englishman had impressed on the right flank.
Hearts then used their first switch and replaced Watt with Arnaud Djoum.
Saints thought they had doubled their lead as Liam Craig capitalised on a loose Hamilton distribution and struck for distance, but the keeper punched the ball over himself but not the bar before clawing it off the line. Still 1-0.
Robbie Nielson brought on Conor Sammon for Johnsen as he looked to get back into the game after 71 minutes.
Robbie Neilson was sent to the stands after 76 minutes, as Saints brought on Chris Kane for goalscorer Cummins.
Hearts’ last switch was to bring on Muirhead for Don Cowie.
Callum Paterson gave Saints a late scare with a bullet header which came back into play off the crossbar only to be struck into the side netting by Muirhead.
Saints final substitution was to bring on Blair Alston for MacLean with a minute to go as Saints looked to hold on.
Chris Kane almost doubled the lead in injury time as a Shaughnessy clearance beat everyone, but he could only toepoke it into Hamilton’s arms.
Paterson skewed a late chance for the visitors, but it finished 1-0, back to back wins and an excellent result for Tommy Wright’s side. Full time: St Johnstone 1-0 Hearts.
Saints: Clark, Shaughnessy, Easton, Anderson, Foster, Paton, Davidson, Craig, Coulson (Wotherspoon, 65), MacLean (Alston, 89), Cummins (Kane, 76). Unused subs: Mannus, Gormley, Thomson, Comrie.
Goals: Cummins (57)
Hearts: Hamilton, Paterson, Rherras, Rossi, Kitchen, Walker, Nicholson, Souttar, Cowie (Muirhead, 83), Johnsen (Sammon, 71), Watt (Djoum, 68). Unused subs: Noring, Ozturk, Buaben, Smith.
Attendance: 5456 Referee: John Beaton Man of the match: Zander Clark
Match report by Ross Gardiner.
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