The Argentine, who is trying to capture his second title this season after winning in Marseille, cruised through the first set, winning it in 39 minutes.
But Verdasco picked up his game in the second set and pushed Del Potro to the limit, only losing in a very close tiebreak. The Spaniard had his chances throughout the match, but couldn’t convert any of the six break points he had.
Del Potro, who reached the semifinal here last year, will play Denis Istomin of Uzbekistan next, who surprisingly defeated world no.5 David Ferrer.
It just wasn’t Ferrer’s day as he went out to Istomin in straight sets 6-4 6-3. It was only the second loss of this season for the Spaniard, who has claimed three tour titles this year so far.
Istomin has had a good season too, he can be happy with a 13-6 match record in 2012.