Djokovic masters Del Potro to secure Shanghai title Sun Oct 13, 2013 8:06am EDT (Reuters) - World number two Novak Djokovic produced a magical display to overcome the ferocious hitting of Argentine Juan Martin del Potro and successfully defend the Shanghai Masters title on Sunday. The Serbian triumphed 6-1 3-6 7-6 (3) to complete a brilliant fortnight on the Chinese hard courts after his victory at the China Open in Beijing last week. Djokovic dominated the court in the opening set, stepping in and moving his tall opponent around as he broke Del Potro twice to clinch it 6-1 in 30 minutes. Former U.S. Open champion Del Potro finally found his form at the start of the second and began to unload a series of heavy groundstrokes to push Djokovic back behind the baseline as he broke for a 3-0 lead. Djokovic had three chances to break back at 2-4 but the Argentine's monstrous forehand provided some clean winners as he crucially held before serving out for the set in the next game. A tense third was on serve and heading for a tiebreaker when Djokovic forced two match points at 6-5 only for Del Potro's forehand to once again dig him out of a hole. But he could not repeat the trick in the tie break as Djokovic sealed victory 7-3 by sending a backhand winner down the line. Writing by Patrick Johnston in Singapore; Editing by John Mehaffey