Germany coach Joachim Low has revealed he is toying with the idea of switching the 85-cap veteran to the left side of defence as he attempts to balance his backline.
The experiment is set to begin in Thursday's friendly against Israel with Lahm's Bayern Munich team-mate Jerome Boateng slotting in at right-back.
Low will decide whether to employ his late tinkering on a more permanent basis next week, with their first Euro 2012 game against Portugal on June 9 in Lviv.
"Against Israel Philipp will start on the left because I want to try something out but it means nothing as to how we will play against Portugal in the first group game," Low told a press conference.
"The decision on [where he will play at the Euros] will be taken next week.
"I see this game as a test for us because I want to try a few things to see how some players adapt to them."
Low's tactical change comes after his side lost a 5-3 defeat to Switzerland at the weekend, when he rested his Bayern stars after their involvement in the Champions League final.
With first-choice Holger Badstuber therefore absent, Mats Hummels and Per Mertesacker were paired at the heart of defence and, despite struggling, Low is confident of their ability.
"It may not have worked 100% in the co-ordination between [Mertesacker and Hummels] but the two can work outstandingly together," he said.
"All three play at a very good level as central defenders at the highest level internationally. We are in a position where they all fit well together, no matter who plays.
"What we need to do now is fine-tune those little nuances."
While Low is set to make changes for the Israel game, their last before they travel to Ukraine and Poland, he reiterated his desire to complete their preparations with a win.
"A good result, no doubt, is desirable as it would give us the push toward the tournament," he said.
"But the Euro euphoria with fans and in Germany will start climbing next week, regardless of the result against Israel."