Wednesday night's FA Cup defeat against Norwich City highlighted the huge problem Jose Mourinho has to contend with at Tottenham at present.
Leading 1-0 thanks to Jan Vertonghen's early header, the Canaries upped the tempo and duly equalised in the 78th minute as Josip Drmic capitalised on a Michel Vorm clanger.
Daniel Farke's team really pushed on after the break and it was clear for all to see that a number of the Spurs side were on their last legs.
Steven Bergwijn was the first to depart in the 54th minute as Gedson Fernandes replaced him, with Lucas Moura following 16 minutes later as Erik Lamela entered the fray.
Both Bergwijn and Lucas have played an awful lot of football over the past couple of months and it is now catching up with them.
The duo both requested to come off as they feared they were going to injure themselves and Spurs are perhaps very lucky that they haven't joined Harry Kane and Son on the sidelines.
Bergwijn, who is still getting used to the demands of English football, isn't used to a hectic schedule following his time at PSV, with Lucas now playing more football than ever at Spurs having been in and out of Mauricio Pochettino's side prior to Mourinho's arrival in N17.
It isn't just the duo who also need a rest as Dele Alli and Harry Winks also came off late on as the head coach looked to freshen things up.
Giovani Lo Celso was one of the players to play the full 120 minutes against Norwich but he could barely move towards the end of the game.
Troy Parrott had been introduced in place of Alli but he wasn't used in his usual role up top as the Argentine had to play there as he just couldn't keep up and operate in the middle of the park.
Without key players such as Kane, Son and Moussa Sissoko at present, there is the real issue of some of the team totally burning out as they look to push on and seal a top-four finish.
In order for that to happen Spurs do need to play their strongest team over the remaining games, yet that's not always going to be possible for Mourinho as he simply has to give some of his team a much-needed breather before the situation worsens.
football.london asked about Lucas and Bergwijn's fitness at the head coach's press conference and he confirmed that both are "buts" for the Burnley game following their substitutions in midweek.
"So yes there are buts behind them, but they have to play," he stated. "They have to play. If not we are throwing away our chances of winning matches. So we have to go with them.
"We have to analyse how, we have to analyse if both at the same time and go with everything we have from the beginning, keep them on the bench and the game plan is to try to go later or split minutes between them.
"We had to try to find the best strategy to try to win matches, but also to give the players the best chance to perform."
Given a Champions League Round of 16 second leg clash against RB Leipzig is on the agenda after the trip to Turf Moor, it may be a case of starting one and naming the other on the bench.
What the Lilywhites cannot afford to happen is to start both and one pulls up injured, thus making their slim chances of progressing out in Leipzig even harder than they already are.
It's not just Lucas and Bergwijn who Mourinho will need to make a decision over as usual midfield pairing Winks and Lo Celso are also due a well-earned breather.
Oliver Skipp proved in midweek against Norwich that he can step up and make an impression, with Tanguy Ndombele desperate for the chance to show what he can do from the start.
Serge Aurier and Davinson Sanchez can also be added to that big list having also played a lot of football recently with very little time to rest and recover.
As crucial as the game is at Burnley on Saturday, the following fixture at RB Leipzig is more important and Mourinho and his coaching staff will definitely have one eye on that.
Spurs cannot let their injury list increase even further and that means key players, regardless of whether the boss likes it or not, have to be rested.
As bad as it has been over the past few weeks, it doesn't even bear thinking about if Lo Celso or another attacking option hobbles off and plunges a top-four finish into further doubt at such a vital stage in the season.
