Everton boss Roberto Martinez hailed matchwinner Romelu Lukaku after victory at West Ham United.

The 20-year-old, on loan from Chelsea until the end of the season, nodded home the 84th-minute winner but his overall contribution was just as crucial.

"Romelu is the type of striker that influences everyone around him because of the gaps he creates. Other players around him become a threat," Martinez said.

"The goal is everything that typifies him - the character and desire to want to be successful. That's why he will be such a big asset.

"He's a very intelligent footballer and I want him to continue enjoying his football because his potential is incredible."