His triple change ten minutes into the second half turned this match in the visitors’ favour, substitute Ellis Simms opening the scoring before Cammy Devlin converted his first goal since moving to Scotland last August.
St Mirren coped well up until that point despite losing midfielder Conor Ronan after only 22 minutes. He received a red card for serious foul play on Beni Baningime despite stern protests from the home support.
Neilson’s decisive substitutions saw him eclipse Stephen Robinson in the Northern Irishman’s first match in charge in Paisley. The changes proved the catalyst for an important 2-0 Hearts win following a sequence of only one success in six league fixtures.
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Neilson made six alterations to his starting line-up from last weekend’s defeat at St Johnstone, while Robinson kept the home line-up unchanged. The hosts’ positive start included two Liam Boyce headers which were both saved by Jak Alnwick in the St Mirren goal.
Barrie McKay was again influencing Hearts’ attacks into a stiff Paisley breeze. Their cause was helped by Ronan’s dismissal following a high challenge with studs showing on Baningime.
St Mirren appealed for a penalty on 34 mintues when striker Alex Grieve fell inside the box but to no avail. Their numerical disadvantage created yet more space out wide where McKay, Gary Mackay-Steven and occasionally Stephen Kingsley gained ground for Hearts.
The latter two both delivered inviting crosses before half-time which were not pounced upon. Referee Greg Aitken incurred the wrath off the locals with a series of first-half calls in the Tynecastle side’s favour but at the interval the scoreline remained goalless.
Another opportunity arose when a cross ball landed at Boyce’s feet early in the second period. Alnwick repelled his point-blank shot and reacted outstandingly to block the rebound as well.
Hearts were struggling to break their hosts down until Neilson’s intervention helped seize the initiative. Shortly after Simms, Ginnelly and Cochrane were introduced, Simms broke the deadlock.
McKay was the instigator with a run and low cross from the left flank. When Charles Dunne scuffed his attempted clearance near the six-yard line, Simms was in place to strike. The excellent Alnwick stopped the on-loan Everton striker’s first attempt but not the second and the ball nestled in his net.
The second goal three minutes later in somewhat more controversial circumstances. Simms sprinted for Baningime’s through pass and collided with Alnwick in the act of shooting as the keeper dived at his feet. The loose ball was tucked into the net by Devlin as referee Aitken ignored St Mirren’s appeals for a foul with Alnwick floored.
Hearts supporters spilled into the track behind the goal as Devlin celebrated his first goal in maroon. At 2-0 ahead, their team were in complete control.
Simms struck the crossbar moments later in what was a superb cameo performance, but Hearts didn’t require a third goal. Two was sufficient.
St Mirren (4-2-3-1): Alnwick; Fraser, Shaughnessy, Dunne, Tait; Power (Brophy 69), Gogic; Kiltie (Flynn 62), Ronan, Jones; Grieve (Main 62).
Hearts (4-2-3-1): Gordon; Atkinson (Cochrane 55), Souttar, Halkett, Kingsley (Halliday 69); Devlin (Haring 69), Baningime; Woodburn (Simms 55), McKay, Mackay-Steven (Ginnelly 55); Boyce.
Referee: Greg Aitken.