Northern Ireland striker Kyle Lafferty only worked on an exercise bike during the opening stages of Wednesday's training session, having hobbled off with a groin problem on Tuesday.
The 28-year-old watched from a machine on a balcony as the rest of Michael O'Neill's squad went through drills at their base in Saint-Georges-de-Reneins, with Craig Cathcart joining that main group for the first time in France since suffering a back injury in Slovakia.
On Tuesday O'Neill had insisted there were "no major concerns" over Lafferty's fitness ahead of their Euro 2016 opener with Poland in Nice on Sunday, but he left the bike at the end of the section open to the media and walked back inside gingerly.
Lafferty had scored seven goals in qualification to fire Northern Ireland to their first major international tournament in 30 years and all eyes will be on the striker's condition to see if it improves ahead of the weekend sojourn to the French Riviera.
O'Neill had attempted to quash suggestions there could be a serious issue when he spoke after training on Tuesday.
"It's fine, it's precautionary, we have no major concerns there," he had insisted. "It's a little twist, but on examination we don't expect any major issues at all.
"We're just being careful, we're more concerned about the thunder and lightning, to be honest!
"He just twisted it a little bit there when he slipped, the pitch is hard. Those little situations are always liable to happen, no major concerns there at all."
While Northern Ireland sweat on Lafferty's fitness, Cathcart was able to provide a positive report on his own condition following the session.
"It's fine," he said of his back problem. "I managed to get through the session today fairly pain free. I've still got that little bit of pain there but hopefully that will settle down over the next couple of days and I'll be ready to go for Sunday."
Having occupied an exercise bike himself on Monday and Tuesday rather than training with the main group, the defender knows that playing it safe is the best course of action for Lafferty too.
"I think he just sat out today as a precaution; I think he'll be fine for Sunday," he added. "It's just one of those things, he has to look after himself."
Were Lafferty to miss out at the weekend, Northern Ireland are ready to call on Will Grigg as a replacement.
The Wigan forward, who has scored once in eight international appearances, is down the pecking order in O'Neill's attacking arsenal, yet his 28 goals for his club side this season has meant he's arrived in France as his country's in-form striker.
And he admits it would be extra special to hear his viral song "Will Grigg's on fire" go from the DW Stadium terraces to the Stade de Nice stands.
"It would be brilliant, that would be definitely be a long way from hearing it at home in Wigan," he said.
"It would be surreal. If I get some time on the pitch, to hear that song would be brilliant. We've got to give the fans a reason to sing about it first."