First-half strikes from Stefano Mauri and Felipe Anderson gave Lazio a two-goal advantage at the Stadio Olimpico on Sunday, but Roma came surging back after the break - with veteran talisman Totti leading the charge.
Having levelled three minutes after the interval, the 38-year-old executed a superb volley shortly after the hour to earn Roma a point.
Totti then stole the headlines around the world by taking a selfie in front of Roma's fans in celebration of his equaliser.
Head coach Garcia was delighted the performance of his whole team in the second half, but paid special tribute to his skipper.
"Totti has strokes of genius because he is a genius," the Frenchman told Sky Sport Italia. "He said beforehand that this was his game and he was right."
The point moved Roma level with leaders Juventus at the top of Serie A for a few hours at least, with the reigning champions facing Napoli later on Sunday.
And Garcia believes their dramatic derby comeback will give his side a huge boost in their quest to claim a first Scudetto since 2001.
"When you draw 2-2, it's better to be 2-0 down and fight back than the other way round. The lads played a great second half and reacted so well," he added.
"The first-half system was also good, but the only problem was that [Miralem] Pjanic was too deep and we needed to push Totti into the box.
"I told the squad at half-time that this game was not over and they proved me right by getting a 2-2 result."
