The 2009 U.S. Open champion made a winning return to the tennis court at the Delray Beach Open Tuesday after 11 months out with a wrist injury.
The Argentine, who has plummeted to 1,041 in the world rankings following his spell on the sidelines, eased past world No. 59 Denis Kudla in his first match since March 2015.
The former world No. 4 saw off American Kudla 6-1 6-4 in 61 minutes, losing just 10 points on his serve, to book his place in Thursday's second round where he will come up against Australia's John-Patrick Smith.
It's clearly early days but the Argentine thinks he might be still capable of troubling tennis' established stars.
"I think winning a match after 11 months is the gift of the tournament for me," Del Potro said on the ATP World Tour's official website
. "For me it's like winning a very important match in my career."
"I'm so excited to keep working because I'm feeling if I do well and if I stay healthy my tennis will be behind me and maybe I can be dangerous one day again," the 27-year-old added.
Long road to recovery
It has been a tough few years for Del Potro, who also missed much of 2014 -- playing just four tournaments -- due to problems with his wrist.
He underwent a third operation in June last year, with his return this week in Florida his fourth attempt at a comeback from injury.
"I think the only thing to do is work hard and if you do before a tournament you have more chance to feel good," said Del Potro, who won the Delray Beach Open title in 2011.
"I have a great family and good friends who support me all the time. They were watching my match on TV in Argentina; it's very late there. I know they're very proud of me. They know how sad I was in the past."
While Del Potro advanced to the next round in Florida, first seed Kevin Anderson was forced to retire from his match against Austin Krajicek due to a shoulder injury, with second seed Bernard Tomic then losing to Rajeev Ram 7-6 6-1.