Chacarra claims Indian Open for first DP World Tour win
Chacarra, 25, came into the final round as overnight leader but slipped after carding a double bogey on the first and a bogey at the third round at the DLF Golf and Country Club near New Delhi.
But a burst of birdies at the sixth, ninth, 11th, 12th and 14th holes saw bounce back to open up a four-shot lead.
Chacarra finished on four under par, two shots clear of Japan's Keita Nakajima, who won the title last year, in second place. Joost Luiten of the Netherlands was another stroke back in third.
"Man it was a tough day," Chacarra said after the win. "We knew it was going to be a long day, going be a lot of pressure and I didn't have the start that I really wanted."
Chacarra survived a late scare on the 17th hole when he found himself near the long grass after his second shot but escaped with a bogey.
He closed his round with a par for a comfortable win in the end as he raised his hands to a cheering crowd.
Chacarra was playing on a tournament invitation this week.
"It means everything, I stayed patient," he said. "I know when I play my best, I'm one of the best players in the world. I already proved that a million times."
"I surround myself with good guys, have a good team. They trust me. My family probably didn't sleep tonight. It's just awesome. It is going to need to sink in, but really proud and I'm just, just happy."
Italy's Andrea Pavan made Sunday a memorable day with a hole-in-one at the par-three 12th from 189 yards.