Cristiano Ronaldo is a certified G -- so says Alexi Lalas ... who's slamming the soccer superstar's "pretty boy" rep after witnessing his badassery this past weekend.
"Anytime there's an athlete that bleeds and plays through it ... they get a little street cred," Alexi told TMZ Sports.
You remember the carnage -- Ronaldo dove in for the header in Real Madrid's match against Deportivo ... scoring a goal, but taking a cleat to the dome in the process.
The collision left Cristiano a bloody mess .