As well as the Europa League, Tottenham are also in the FA Cup and have a 1-0 lead against Liverpool in the semi-finals of the Carabao Cup.
A win at Hoffenheim means Tottenham can go through to the knockout stages if they win at home to Elfsberg next week.
The game comes a long time ago for Spurs as they travel to Liverpool in the EFL Cup on February 6 before traveling to Aston Villa in the fourth round of the FA Cup three days later.
They have crucial league fixtures against Leicester, Brentford and Manchester United as they look to avoid dropping lower than their current 15th place in the Premier League.
“It’s a massive couple of weeks for the club,” added Hargreaves.
“It defines their season with the second legs of the FA Cup and League Cup.”
Former Tottenham striker Peter Crouch said: “They are one game away from the final.
“They’re on the rise there. If they get to the finals, that’s a good season.”
Tottenham are now among the favorites to win the Europa League.
A top four finish is unlikely, with success in Europe’s second tier competition the best way to ensure them Champions League football next season.
“The Europa League is their priority now,” added Crouch.
“I look at the teams and they are capable of beating any of them.”
