The Scot has often flourished on tough courses throughout his career, and showed he had the measure of DLF Golf and Country Club last season as he recorded a top ten finish in New Delhi.
Fast forward 12 months and a sensational putt from off the green at the last handed him an eagle, a score of 67 and a one shot advantage at five under.
South African Christiaan Bezuidenhout, Swede Robert Karlsson and Spaniard Pablo Larrazábal were his nearest challengers, a shot ahead of England’s Ashley Chesters, Australian Scott Hend, Japan’s Masahiro Kawamura, Thai Prayad Marksaeng, Italian Edoardo Molinari, home favourite Shubhankar Sharma and South Africa’s Erik van Rooyen.
Gallacher was part of an early eight way tie for the lead on a congested leaderboard and broke out of that group with a birdie on the ninth that saw him turn in 33.
Further gains were to follow on the tenth and 11th and the 44 year old had a two shot advantage but a double bogey on the treacherous 14th dropped him back into a six way share.
Kawamura made an eagle, two birdies and a bogey on the front nine, and another gain on the tenth briefly saw him take the lead on his own but he gave the shot straight back on the next.
Bezuidenhout turned in level par and after making gains on the 11th and 12th, he recorded a bogey on the next. He then birdied the 14th and 16th to make it a seven way tie at the top.
Søren Kjeldsen was the next man to break out of that group as he had a roller coaster of a back nine after turning in 35. The Dane birdied the tenth and 11th, bogeyed the 12th, but picked up shots on the 13th and 15th to hit the summit.
Sharma had been a picture of consistency with birdies on the 12th, 18th and first and when he put his approach from 252 yards to seven feet on the par five fourth, he had leapfrogged into the lead.
A bogey from Kjeldsen on the 16th briefly handed the two time European Tour winner a two shot advantage but there would soon be a four way tie at four under.
Molinari hit a stunning approach into the sixth to add to birdies on the 11th, 14th, 15th and 18th, and a bogey on the 16th, while Kawamura made another gain on the 13th.
A wonderful tee shot into the par three 17th handed Kjeldsen another birdie and Sharma hit a poor bunker shot and followed it with a poor chip to surrender a shot on the sixth.
A ten foot putt on the last from Bezuidenhout saw him set the target and make it a five way share but Gallacher soon leapfrogged them all. The 2014 Ryder Cup star was off the par five 18th in two but holed that very long putt for an eagle and the clubhouse lead.
Playing partner Kjeldsen made a triple bogey to go tumbling back, while Molinari double bogeyed the eighth after finding the water but ended his round with a birdie.
Larrazábal had been part of the very early logjam for the lead after a birdie on the 11th and a two on the par four 13th but he failed to make up more ground with birdies on the 18th and fourth and bogeys on the 14th, first and sixth.
Gains on the seventh and eighth then catapulted him into a share of second where he was joined by another fast finisher in Karlsson.
The 2008 European Number One turned in 34 with four birdies and two bogeys but then dropped shots on the first, third and fourth. A birdie on the sixth got him back to level par and he pitched in at the par four seventh before making a three at the par five eighth for a pair of eagles.
Sharma dropped another shot on the seventh after finding sand off the tee and he slipped back into that group at three under alongside Kawamura, who made a bogey on the 15th.
Last week’s winner Hend bogeyed the 17th and made a triple on the next but also had seven birdies to sit two shots off the lead.
Van Rooyen had eight birdies but also made a double and three bogeys, Chesters dropped two shots with five birdies, and Marksaeng recovered from an early bogey on the second with four gains on the back nine.