Several challenges on visiting winger Gary Mackay-Steven left Neilson unhappy despite his team going top of the cinch Premiership with two victories from two games.
An early elbow from Greg Kiltie floored Mackay-Steven and another second-half tackle from Charles Dunne left him in agony on the turf. Neilson was then cautioned by referee Gavin Duncan for protesting.
The St Mirren substitute Kristian Dennis received a late red card for elbowing Peter Haring, and Neilson felt the situation got out of control.
“I don't want to complain too much but a few of the challenges weren't acceptable, especially the one in the first minute where there’s an elbow in his face. The fourth official is five yards away and doesn’t give anything,” said Neilson.
“Flair players are going to get smashed, that’s just what happens in Scottish football. I don’t like it. It happened 15 or 20 years ago but nowadays you should be doing it. It’s getting better but when we go into Europe, Scottish players go and smash people and they get sent off.
“That challenge for me just isn’t good enough. Gary is technically a brilliant player and the only way a lot of teams will stop him is just by trying to smash him. Even one where he gets injured and I get booked, if that’s how the referee wants to deal with it then we just need to deal with it.”
Andy Halliday and Liam Boyce scored Hearts’ goals to end a nine-year wait since their last win at St Mirren, which came in the 2012 Scottish Cup. Defensive resilience helped them see the game out under intense pressure and move three points clear at the top of the league.
“I’m pleased with the start but we keep emphasising it’s just a start,” added Neilson. “We go to Celtic Park next Sunday in the League Cup after two good results. It was 2010 last time we won here [in the league] and it’s a very difficult place to get three points.
“I watched a lot of St Mirren and they have a lot of cohesion because they’ve kept a lot of players for the last couple of years. They all know each other’s game and they cause problems because they have physicality and pace up front.”
Reserving praise for Boyce, Halliday and Alex Cochrane, Neilson went on. “Liam started up front, then back into No.10, then back into midfield, then back up again and eventually we took him off. He’s very adaptable. He will pick up pockets and get the ball. I thought Andy Halliday did well as well. I asked him to play wing-back and it was a great finish for his goal.
“We knew St Mirren would have the ball at times. As soon as you step out to press they bang it over the top. I thought our back three did very well, especially a young boy like Alex Cochrane against the physicality of [Curtis] Main and [Eamonn] Brophy.
“Alex can play wing-back, left-back and left centre-back. As a pair, the two St Mirren strikers are one of the best pairs in the league because they work so well together.”