Ferrer dropped behind Jo-Wilfried Tsonga to sixth last week after about six months at the No. 5 ranking but posted his third win in four tournaments this year by taking the Abierto Mexicano Telcel event in Acapulco without dropping a set in taking back the higher ranking.
Ferrer is 18-1 on the year, with the only loss coming in the quarterfinals at the Australian Open to world No. 1 and eventual tournament champion Novak Djokovic.
Del Porto is 16-4 in 2012 but 0-3 versus Roger Federer, who defeated del Porto in the semifinals in Dubai last week. Still, del Porto pulled in enough points to move to ninth in the rankings with Janko Tipsarevic now 10th.
Djokovic has 13,310 rankings points, safely ahead of No. 2-ranked Rafael Nadal at 10,415. Federer, who ended up winning at Dubai for his 72nd ATP title, is No. 3 at 8,710 and Andy Murray, the Dubai runner-up, is fourth at 7,450.
Ferrer has 4,665 rankings points, 210 more than Tsonga. Tomas Berdych (3,860) remains seventh and Mardy Fish (2,875). Del Porto is just 35 points behind Fish and Tipsarevic has 2,710 points.
The ATP's third winner last week was Kevin Anderson, who is up six spots in the rankings this week to No. 30, which matches his career high.
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