Chelsea manager Thomas Tuchel hailed the longevity of Olivier Giroud after the striker struck a fine winner against Atletico Madrid in their Champions League last 16 first leg on Tuesday.

The France international produced a wonderful overhead kick in the 68th minute to secure a 1-0 victory at Arena Nationala in Bucharest, with coronavirus travel restrictions preventing the tie taking place at the Wanda Metropolitano.

While 34-year-old Giroud had to wait for a lengthy VAR check, the goal was eventually given and it was his sixth in the competition this season after a crucial late effort at Rennes and a four-goal haul at Sevilla in the group stage.

Tuchel said: "If you see him on a daily basis, you cannot be surprised. He is totally fit, his body is in shape and his physicality is on top level.

"Mentally I have really the feeling he enjoys every day being a professional soccer player on this level and this is the level he needs to be.

"He trains like a 20-year-old, like a 24-year-old. He is a guy who has a good mixture of serious and joy in training. He is always positive and it is a big factor for the group.

"He starts, when he comes from the bench, he has all these qualities and it is good like this."

Giroud, who did not play a single minute at Southampton last weekend, was one of four changes made by the German with Callum Hudson-Odoi also handed a start despite being substituted after only 31 minutes at St Mary's following his half-time introduction.

Chelsea recovered from a nervy opening few minutes in Romania to dominate the majority of the contest and prevent LaLiga leaders Atletico from having a single shot on target.

The Blues boss added: "I am super happy for my players and the team for such a big reward. We actually can read it on the scoreline that we have the result against top opponents.

"It was very important that we are absolutely concentrated over all 96 minutes and that we also accept that it's very hard to create chances, but we did all that and it was a very good team effort."

A negative for the Premier League club, who are unbeaten in eight games since Tuchel replaced Frank Lampard on January 26, was cautions for Mason Mount and Jorginho which will rule them out of the second leg.

With the upper hand in the tie, especially with the away goal, the 47-year-old stressed the importance of Chelsea not becoming "lazy" during the next three weeks before the return meeting at Stamford Bridge on March 17.

"We will miss two crucial players, it makes things not easy for us, but I am very happy with the performance of everybody," Tuchel insisted.

"Honestly, we now play Man Utd, Liverpool, Everton and Leeds; it is good like this. We cannot get comfortable, we cannot get lazy. These games will push us to our limits, then we will think about our solutions for the second leg."

Atletico were without several players, including the suspended Kieran Trippier, and struggled in unfamiliar surroundings to suffer a second straight defeat following Saturday's 2-0 loss to Levante.

It is now one victory in five games for Diego Simeone's side and he said: "I understood we had to play like this.

"I think the main problem was we didn't have a lot of precision about taking back the ball.

"It was a hard game, no one had a lot of chances of scoring but also it was very difficult with their attack because they have really strong and quality players."