Spain's world number three David Ferrer, however, had his bid for a fifth Auckland Open title ended in the semi-finals by a 6-4 7-6 (7-4) defeat to unheralded Taiwanese Lu Yen-hsun.
While Simon, seeded 18th at the Australian Open, will have scans on the injury, Gasquet meets world number seven Tomas Berdych in Saturday's final.
Lanky Argentine Del Potro, who will be seeded fifth in Melbourne, hit nine aces as he brushed aside the Russian fourth seed 6-4 6-2 in just over an hour to reach his seventh final in the last 12 months.
Two of those finals were at Masters events in Shanghai and Indian Wells, an indication for some that Del Potro might be returning to the level of form that he reached to win the 2009 U.S. Open title before a wrist injury nearly ended his career.
The 25-year-old will meet Australian defending champion Bernard Tomic, who came from behind to beat Ukrainian qualifier Sergiy Stakhovsky 6-7 (4-7) 7-5 6-3, in Saturday's final at Sydney's Olympic Park.
Del Potro was seeded to meet world number one Rafa Nadal in the quarter-finals of the year's first grand slam, while Tomic was revealed as the Spanish 13-times grand slam champion's opponent in the opening round in Friday's draw.
World number five Del Potro and Australian veteran Lleyton Hewitt are the only grand slam winners apart from Nadal, Roger Federer, Novak Djokovic and Andy Murray still active in men's tennis and the Argentine believes he might soon be challenging the leading four players again in major finals.
"I think I'm getting closer to the top four guys," he said on court.
"They are still playing such great tennis but if I am fit, I will try to be dangerous for them."
At the Auckland Open, world number 62 Lu stunned Ferrer in two sets to bring the Spaniard's 14-match, three-year winning streak at the tournament to an end.
Lu will face big-serving American John Isner, who came from behind to beat Spain's Roberto Bautista 3-6 7-6 (7-2) 6-4, in his first ATP final on Saturday.