Mel sees red over Van Persie
Just three minutes after Van Persie was booked for a tackle from behind on Morgan Amalfitano, the Manchester United striker took out Steven Reid with a two-footed sliding tackle.
Moss awarded a foul, but did not produce a second yellow and Van Persie was allowed to remain on the pitch.
The Baggies were just 1-0 down at the time and Mel thought his team would have stood a good chance of taking something from the game if Van Persie had been dismissed.
"It was a clear second yellow card," the under-pressure West Brom manager said.
"I didn't speak to the referee after. There was no point, but with the red card to Van Persie, the game would have changed and been completely different."
United boss David Moyes disagreed with Mel's opinion, but was not willing to take any more chances with Van Persie and he hauled the player off moments later.
Van Persie reacted with disappointment when his number came up on the fourth official's board, shaking his head before sauntering off the pitch.
The United boss insisted his striker was always aware that he would not play the full game, however.
"Robin knew exactly what was happening. I told him. I walked over and told him that I was going to have to take him off," the United manager said.
"It was a foul (against Reid) but it was not a second booking.
"It made my job easy. He played 90 minutes for Holland in midweek and I was never going to play him for another 90 minutes today."
A fabulous finish from Danny Welbeck rounded off the win for Moyes' side, who moved up to sixth in the Barclays Premier League.
Mel can only dream of being in such a high position in the table.
Seven matches have passed since he was appointed and he is yet to achieve his first win.
The Baggies are one point above the relegation zone, but the team below them - Sunderland - have two games in hand.
Mel is sure he is the right man for the job.
Doubts persist about whether the Albion hierarchy feel the same way and Mel admitted he had no idea whether the club were about to axe him just two months after his appointment.
"It doesn't depend on me," the former Real Betis manager said.
"The only thing I am thinking about is working tomorrow and putting all my energy into making sure West Brom win at Swansea.
"Of course I am sure (I can keep West Brom up). The next four matches are very important for us. We need 11 men, 11 good professional players and a good mentality. It is the future of the club (at stake)."
Moyes also raged at the officials from the touchline when West Brom goalkeeper Ben Foster was not sent off for handling the ball outside the area, but he was a happy man when he left the Midlands following what turned out to be a relatively easy win.
Eleven days after a morale-sapping defeat to Olympiacos, his team put on a much better display that moved them to within nine points of fourth place.
"All areas pleased me today," Moyes said.
"There were some very good performances. Marouane Fellaini did really well, Phil Jones and Chris Smalling were excellent. I thought the two boys up front were fabulous, with Juan (Mata) and Adnan (Januzaj).
"I saw by their attitude had changed completely (from the Olympiacos game).
"They showed their effort and commitment, not just good play."
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