Newcastle United head coach Steve McClaren was unhappy to see Aleksandar Mitrovic denied a penalty as his side went down to a 1-0 Premier League defeat against West Brom.
Darren Fletcher's late header gave the hosts a crucial victory at The Hawthorns on Monday and meant Newcastle remain inside the bottom three after a third consecutive match without a win.
McClaren felt referee Mike Jones' decision not to award his team a spot-kick in the second half when Mitrovic was attempting to shoot at goal under pressure from Jonny Evans was the moment that decided the match.
"It is a game of fine margins," the former England manager said to Sky Sports.
"There was always going to be one goal in it - it seemed that way. I thought we started every so well, created good chances and could have scored first.
"In the second half as well we started very well and it is about decisions. I am afraid I think the referee will look back and think 'I got that decision wrong' for the penalty on Mitrovic.
"He [Evans] has manhandled him the area, put him off his shot. I have seen it so many times now, it is unbelievable.
"Then at the other end they go and score the vital goal and we have had nothing from the last two games.
"I haven't spoken to the referee. At the time Mitrovic looks as if he was complaining of being pulled back and it looked like it, but I have just seen it again two or three times on the replay and those decisions cost you.
"I know it is difficult being a referee and you have to make snap, quick decisions but he will look back and say he has got that one wrong and it has cost us three points."