The Blues captain netted a double in Wednesday night's 3-0 win at Fulham and along with fellow centre-half David Luiz, secured a vital three points for the Stamford Bridge side, and posing some selection problems for the Spanish tactician.
"All the team did well but the defenders in particular were working hard against good strikers. Both David Luiz and John were really good," he told Sky Sports.
"It's coming back. If he can train every week it will be easier for me to pick him every week and we have competition. It is good for us and a problem for me."