Martin, suffering from a fractured scaphoid since he crashed on stage one, will race stage 9's 41.5km time trial between Arc-en-Senans and Besancon as a test of his time trial position and looking towards the Olympics.
"He's doing all right this morning, we did another x-ray and he seems to be ok," Omega Pharma-Quick Step doctor Helge Reipenhof told Cyclingnews at the stage four start. "The fracture is exactly the same so there is no need to worry about a possible abandon because of the injury.
"We also gave him a new brace yesterday evening [for the injury] to adapt to the swelling because the soft tissue in the area is expanding, but I'm very confident that he will get through today's stage.
"We'll take it day by day and see if he can get through to the Besancon time trial, literally just to see how he feels on a time trial bike in competition. It's something we want to try before the Olympics."
Although this year his injury will cloud the strategy, it is not entirely new for Martin: as the reigning time trial world champion Martin used the Vuelta time trial last year as part of his build-up for Denmark. He also won the final time trial in the Tour in Grenoble last year.
As for Leipheimer, the veteran American has been flying under the radar so far, but he also has his eye on a Tour time trial, too.
"I'm taking things day by day, so far so good," Leipheimer told Cyclingnews on Wednesday. "Yesterday [stage three] was a day to survive, and I survived, so that's one day, but you never know."
His objectives are "of course, to place as high as possible on the overall classification and be with the best, and you always have to adapt and chance your strategy but that's the goal right now."
Unlike Martin, who is looking towards London, given he's not riding the Olympics, Leipheimer's Tour time trial performances are a goal in themselves.
"I think probably the last one [stage 19 from Bonneval to Chartres, 53.5km] is more suited to me, it's steadier with just one rhythm, you never get out of your position." Fans will recall that Leipheimer won the final time trial stage of the 2007 Tour and in the 2008 Vuelta, in which he finished third and second respectively overall, so there can be no doubting he knows how to hold his form throughout a major stage race.
After winning the early season Tour de San Luis overall then crashing out injured just before the Tour of the Basque Country when he was hit by a car training - the season's "been up and down" was his laconic analysis - Leipheimer, currently in 37th spot 45 seconds back, says that his morale "is better after yesterday."
"[The Tour of] Switzerland [where he finished third] was great, I was a little ill after that, but I came to the Tour and I really wanted to play it safe on that first stage and avoid crashes. It ended up costing me 17 seconds but really I'm not worried about that. The prologue [where Leipheimer was 80th] wasn't great, but I just need a few days to ride into it and yesterday" - where he finished in the heart of the front group behind Sagan - "I felt pretty good.
"It was a nervous day, there were two crashes that happened right in front of me, but I stayed upright." Something which on Wednesday in the backroads of Boulogne-sur-Mer was easier said than done.