Mulumbu: I must make up to my West Brom teammates
The Baggies midfielder has again apologised for his stoppage-time sending-off in the 3-1 defeat at West Ham United.
"I want to apologise again," the DR Congo international told the WBA website. "After it happened I knew it was a big mistake from me.
"Normally I'm calm and I love to play football. I was wrapped up in the atmosphere of the game and I wanted to win.
"I was disappointed. But it's a good lesson for me and I need to move on now. I feel like I've let my team-mates and the fans down.
"I hope I can bounce back and when I come back I need to be fit.
"Four weeks is really long so the best thing for me is to stay fit and focused because there are four games when I'm back and they are hard ones, including both Manchester clubs.
"I didn't want this break - but sometimes it's good."