My 5 cents from a Habs fan who watched last nights game. To be honest spent more time watching what the Habs were doing/failing to do than focusing on individual Leafs players.
That said you can't blame the OT on Matthews-Marner, they never had the puck. They lost the faceoff and Mtl controlled puck until Caulfield took the shot that hit iron. 3-3 OT is often 1st possession wins. You could argue that Leafs should have had the 75% FO guy Last night Tavares take that draw then switch with AM if they won it. Matthews was not good on FO last night. Thats on Keefe for putting him out for that draw
The one play I would criticize Matthews on was the Short handed goal against. He could have won the race to that puck behind the net but did not backcheck hard and let Dach by to get to puck 1st. Still could have hit Dach to separate him from puck but did not. Yeah he was out for most of PP but there was a stoppage in there, tired or not you still have to backcheck. His teammates played it worse probably. Other forwards changed on way back but did not engage defensively instead waiting for puck to exit zone while Mtl had control. Ends up with a 2-1 down low for Monahan and Dach with all day to put it in. Yeah its preseason and Veterans do not push it esp on backcheck but Matthews does that way to often.