West Ham striker Marko Arnautovic was left frustrated after their FA Cup win over Birmingham City.

The Austrian forward, having put the Hammers ahead, was far from happy at being substituted after only 20 minutes at the London Stadium.

Andy Carroll, who had replaced Arnautovic, eventually sealed West Ham's passage with his first goal of the season in stoppage time. Arnautovic may have picked up a slight knock, but he clearly felt it was not going to be a problem and wanted to continue.

Hammers boss Manuel Pellegrini said, “Marko felt a pain in his back and at the beginning he wanted to recover, but he could not continue. It was not good to take a risk as he has just returned after an injury and he played 90 minutes less than 72 hours ago and 65 minutes in the other game, so it was good for him not to continue. There is no problem and he scored a goal!"

Pellegrini was also pleased for Carroll, who ended a 368-day drought with a trademark header, having earlier missed one gilt-edged chance and seen another shot clip the woodwork.

“Andy has a career behind him and he is a player who, when he is playing, something is always happening around him," he observed. “He is coming back after a long injury and I hope he will contribute a lot to our team in the second half of the season.

“Andy has been working with the squad without any problems for three weeks so that's why we are increasing his minutes. Now he played around 70, so we allow him to recover his normal performance after his injury."