"The performance is very pleasing. It is never easy to start a tournament of this magnitude and we looked a team very concentrated for 90 minutes," Martinez said.

"We kept a clean sheet in a very good way and the win will allow us to grow into the tournament."

It was not all good for Belgium, with Martinez admitting the outlook for Leicester defender Timothy Castagne was "really bad" after he suffered a double fracture to his eye socket in a nasty clash of heads with Daler Kuzyaev.

Elsewhere in Group B, Denmark's match with Finland in Copenhagen was suspended for 90 minutes after Christian Eriksen collapsed at the end of the first half and required lengthy medical treatment on the pitch.

The Inter Milan playmaker required compressions to be performed on his chest, but was awake as he left on a stretcher and was reported to be stable in hospital by the Danish Football Association.

Lukaku dedicated his first goal to club colleague Eriksen and Martinez said it was an emotional dressing room.

He added: "We were watching it live and then it was probably in the next five minutes we were going into our team meeting and you can imagine the last thing we wanted to speak was about football.

"It was a real shock, real sadness and there were tears. We have a lot of team-mates in our dressing room that have shared big moments with Christian.

"Our wishes from the national team and everyone in Belgium is to Christian, his family, and the whole Danish team because that was a really tough moment in St Petersburg so I can only imagine how difficult it was in Copenhagen."

Russian boss Stanislav Cherchesov was disappointed at the reaction of his players to Lukaku's 10th-minute opener and also repeatedly dodged questions about the Belgian team being booed when they took the knee before kick-off.

He said: "We started the game as we were planning to. We played in a very compact way and the first goal affected the game and the morale of our team, which I didn't like.

"We had to keep going. We made changes in the second half and played in a more compact way but we couldn't create as many moments as we would have liked."