The mercurial forward swept home a typically emphatic free-kick in a top-of-the-table encounter at Camp Nou on Sunday to send his side eight points clear at the La Liga summit.
That effort was the 600th of Messi’s glittering career, with the five-time Ballon d’Or winner continuing to raise the bar of personal excellence.
Atletico defender Gimenez concedes that the talismanic 30-year-old is unplayable at times, with his latest goal just another example of the unworldly ability one of the all-time greats possesses.
The Uruguayan told beIN Sports: "Messi is from another planet.
"He scored a golazo from a free kick. There is nothing to reproach our team for.
"What we lacked was to start the first half as we started the second.
"If we had done that, the game would have been different.
"More than anything, it was attitude - in the first half, they were all over us. I wish we had a time machine and could begin the first half like the second when the attitude was different and we went for the game."
Messi’s stunning free-kick came just 26 minutes into a heavyweight contest, and his flash of brilliance ultimately settled the tie.
Atletico midfielder Saul Niguez was another to pay homage to the remarkable South American at the final whistle, with “one great moment” separating two title hopefuls in Catalunya.
The Spain international said: "In the first half Barcelona dominated.
"We tried to press up top, but we did not get there. In the second half, just the opposite. More intense.
"Neither of the teams had clear chances. The difference was Messi, [who] decided the game with one great moment. In the second half we were better, but it did not come for us."