Riding third in an eight-horse jump-off in heavy rain at a packed Tops International Arena in the southern Dutch town of Valkenswaard, De Luca produced a clear round in a time of 39.20 seconds, 0.73 faster than Berlin winner Christian Ahlmann of Germany and 1.11 second ahead of local favorite Maikel van der Vleuten.
"It's fantastic to win here," De Luca, of Italy, said in a televised interview after adding the Valkenswaard title to his Shanghai trophy earlier in the season.
Paying tribute to his 13-year-old Belgian bred gelding, Ensor de Litrange LXII, he said: "He tried everything for me. It was quite fast. I'm very happy."
"He was jumping very good in the qualification and he did two more rounds, super. I'm really pleased."
Smolders extends overall lead
Dutchman Harrie Smolders extended his lead in the overall standings of the 15-leg competition for the world's top show jumpers with a sixth place in the jump-off in Valkenswaard.
With just two more events to go, Smolders has 268 points, 11 points ahead of Ahlmann and 13 points clear of Italy's Alberto Zorzi.
Riding second from last in the jump-off under the lights in Valkenswaard, Smolders had watched the competition closely from the warm-up arena. A loud sigh went through the arena after Smolders' 13-year-old stallion Emerald N.O.P. dropped the last fence to finish in a time of 39.58 seconds, which would have been good for second place.
De Luca's win in Valkenswaard meant the Italian leapfrogged London winner Scott Brash into fifth place in the overall standings with 243.5 points.
"It's very good, he won twice this season so for sure he will help me to go a little bit up," De Luca said. "We try our best for the last two."
Valkenswaard -- Home Of The LGCT
Although it had been dry all weekend, the rain came down heavily at the end of the first round, with riders wearing rain coats over their usual riding jackets.
Staging the elite show jumping event for the 12th season, Valkenswaard is the hometown of former Olympic gold medalist and LGCT founder and president, Jan Tops.
Its sprawling, state-of-the-art Tops International Arena has some of the best facilities in the world, including a huge main sand arena with covered seats for spectators.
Although Valkenswaard, a town of 30,000 in the south of the Netherlands, is no match for some of the previous stops of the LGCT including Miami Beach, Cannes and Paris when it comes to glamor, it has managed to attract a number of top riders -- including Jessica Springsteen and Zorzi -- who use it as their training base.
GCL Down To Wire
With only two more legs to go, there was a twist in the team Longines Global Champions League competition after Smolders and Jos Verlooy of Hamburg Diamonds produced three clear rounds to win the two-day event ahead of the all-Dutch Madrid in Motion.
That result meant they knocked Valkenswaard United off the top of the overall leaderboard and now lead the reigning champions by just eight points. Mexico Amigos are in third place on the overall leaderboard at 47 points back.
Rock star Bruce Springsteen and his wife Patti watched their daughter Jessica compete for Shanghai Swans.
The difficult, technical course by course designer Uliano Vezzani was a bridge too far for the 25-year-old Springsteen and her Dutch gray gelding Cynar v as they had 17 penalties on Friday and five more on Saturday, the most of the three-rider Shanghai Swans team, which finished 14th in the 18-team competition.
The next Longines Global Champions Tour will take place at the Stadio dei Marmi in Rome 21-24 September, followed by the finals in Doha 9-11 November.