The British No 1 secured a comfortable 6-1, 6-3 win over the Austrian No 1, Stefan Koubek, in his opening match on Monday but has lost his two previous meetings with the 22-year-old American, which both took place last year.
"I'd certainly like to change things," Henman said. "My record against Gambill is not too positive. But I've got a few things to work hard on and we'll see how the week plays out."
Henman is out of the race for one of the eight automatic places at the season-ending ATP World Championships at Hanover in Germany. And although he could still claim a place as an alternate if he lifts the Stockholm title, that is not a major consideration.
His game has gone off the boil in recent weeks with defeats at the Mercedes Super 9 tournaments in Stuttgart, where he went out in the second round, and Paris, where he went one round better. But Henman, a Stockholm semi- finalist last year and quarter- finalist in 1997, said: "I've always enjoyed it here. I've not achieved a Hanover place this year but my goal now is to finish the season in the top 10."
n At the National Championships in Telford yesterday, the third seed Lucie Ahl comfortably disposed of Scotland's Nicola Payneas in straight sets. The 25-year-old Devon player, a semi-finalist two years ago, cruised through 6-1, 6-3.