Mauricio Pochettino has made many great decisions in his short tenure in the White Hart Lane dugout. How he has transformed Tottenham from fringe Champions League contenders to title contenders in one season has been nothing short of remarkable. But all managers are capable of making mistakes, and against Dortmund on Thursday, he made a classic error and it cost Spurs a chance at the Europa League as well as a chance to prove themselves against one of the best sides in Europe.

He decided to play a massively rotated squad with seven changes from the north London derby at the home of one of Europe’s best teams. This, under most circumstances, is sensible and understandable, considering Spurs still have a legitimate chance to win the title. His focal points have been run into the ground, especially Eric Dier, whose rest consists of playing center back instead of being fully rested. But today, throwing out a midfield of Tom Carroll and Ryan Mason against the insane pressure and pace of Borussia Dortmund was a massive mistake, and also a pretty basic one.

Resting players for the Premier League title challenge ahead is not a bad decision, and after two grueling London derbies in four days, Pochettino has every right to rest and rotate in order to better his side’s chances of finishing in the top four and keeping the pressure on pace-setters Leicester. What that doesn’t mean is throwing out a reserve side that basically tells a first-team Dortmund that you’re giving up on the competition. Pochettino probably knew his side was going to have problems even at full strength, but a dramatically weakened squad featuring players that aren’t nearly at Dortmund’s level was waving the white flag before a ball had been kicked.

Dortmund coach Thomas Tuchel rotated his squad too, but not massively so, and they too are in a title race with Bayern Munich, though theirs is more likely over. And even though their squad is considerably deeper, they have found a way to rotate while not in effect conceding the match for anything on the pitch has taken place. Dortmund are a better team than Spurs, but that doesn’t mean Pochettino’s men could have competed up to that level. They have already this season. And for those wondering if Spurs needed the rest after the north London derby, Dortmund played Bayern Munich to a stalemate just a few hours later last Saturday, meaning that excuse is well and truly neutered.

SEE MORE: Schedule of Europa League games on US TV and live streaming

In order for this result to be justified, Spurs will have to go on and win the Premier League, which is a tough ask. He shouldn’t be begrudged for doing that, but he can be criticized for not giving this chance at a trophy and a chance to prove his young side’s mettle against one of the European giants (and a team they may well play in Champions League next season) what it fully deserves. Unless they play in Champions League next year, we’ll never know whether this Spurs side had a chance to truly match up with Dortmund, best-on-best. The timing of the fixture didn’t play to Spurs advantage, but it’s still a shame that even before the second leg, the tie is basically done and dusted. And it’s not like Spurs needed their best XI to beat Aston Villa away or Bournemouth at the Lane, even though anything can and will happen during this Premier League season.

Prioritizing the league over a Europa League trophy whose prize is equivalent to that of something Spurs will likely get anyway is a sound move, and one that in the long run is probably better. But it doesn’t take away the sting of watching an overmatched squad marched to their death at the Westfalenstadion against a team most of us will never know if Spurs had a chance to actually beat over two legs.

The perils of the Premier League in the modern era affected what should have been a glamorous European tie. And it’s a shame.