It marked a winning start for Atletico at the Estadio Wanda Metropolitano.
"Griezmann is returning to being the club's most decisive player, it was a wonderful goal," he explained to reporters.
The aforementioned goal came at a time when the hosts were running out of ideas in attack, and such was the importance of the goal, as well as the occasion, the Argentine coach allowed his emotions to get the better of him on the sideline.
"I am left with the sensation created by this goal," he admitted. "I will always remember celebrating it with [assistant coach] German Burgos."
The Estadio Wanda Metropolitano had been delayed, yet the wait was worthwhile with Simeone detailing just how impressive an arena it is.
"The pitch looks very big, it is spectacular," he noted.
"The fans are very close and when matches are close, the fans will be able to encourage us."