Reece James suffered a recurrence of the knee ligament injury that ruined his World Cup dream in Chelsea’s first game back after the Qatar tournament break.
The England full-back pulled up in Tuesday’s 2-0 Stamford Bridge win over Bournemouth, and now faces another month on the sidelines.
James’ latest setback adds to long-term injuries for N’Golo Kante, Wesley Fofana and Armando Broja, with Ruben Loftus-Cheek and Ben Chilwell also still working back to fitness.
New Blues boss Potter insists no one will lean on the crutch of an excuse, but did lament an added dimension to an already sizeable challenge in his Stamford Bridge task.
“It’s been a really tough period, as challenging as there has been in my time as a coach,” said Potter.
“But we’re Chelsea and people don’t want to hear those reasons or excuses. We have got to get on with it and try our best to find the answers.
“If you go back to the Newcastle game [before the World Cup], we had no Kepa, no Reece, no Wesley, no Ben Chilwell, we lost Marc Cucurella with illness overnight; then we lost Ruben Loftus-Cheek after two minutes.
“We had no Kante, we lost Cesar Azpilicueta after 20 minutes, and also had no Raheem Sterling.
“That was simply the period we were in, and we still have quite a few guys that are out.
“But that is the challenge of being in multiple competitions, multiple games in a short space of time with the World Cup.
“So it was difficult. Again, I’m not making excuses, I’m just telling you what I think of the situation.
“We have to deal with it. The break hasn’t been a positive one for us and I could have made lots of excuses had the result against Bournemouth not gone our way.
“We had four (senior) players for the first two weeks, then players dripping back in and the break people think we have had to work with the players isn’t there.
“But you can’t make those excuses, you just have to win. And we did against Bournemouth, so that’s good.”