Thomas Tuchel said Romelu Lukaku’s goal against Zenit St Petersburg underlined the Belgian’s status as a world class striker.
It was a difficult night for the holders as Zenit defended well and managed to frustrate them.
But Lukaku’s 69th-minute header from Cesar Azpilicueta’s cross was enough to give Chelsea the win in their opening Champions League group game.
Boss Tuchel declared: “We didn’t create many chances or deliveries but that’s why Romelu is here and that is what makes him a world class striker. You don’t find many strikers of that quality.”
Chelsea were finding the going tough up to that point, although Antonio Rudiger almost put them ahead with a spectacular strike.
“It was tough for us in the first half to create touches in the box,” Tuchel admitted.
The German added: “We played at high intensity and had to be very focused in defence, but in the second half we found space between the lines and created differences.
“The cross from Cesar was very good and it was nice to see the opener.
“The goal changed the whole momentum of the match and Romelu brings the belief and has the personality not to be impatient. He just does what he does.
“I’m happy with how we played and we had energy against a strong opponent who I respect.”
Lukaku’s goal was his fourth in as many matches since returning for a second spell at Stamford Bridge.