Jude Bellingham said it was "fantastic" for Borussia Dortmund to seal their place in next season's Champions League as team-mate Jadon Sancho achieved a feat last accomplished by David Beckham.

At the age of 17, Bellingham has found himself thrust into Bundesliga action at the heart of Dortmund's midfield, and the former Birmingham City youngster could be heading for Euro 2020 duty with England at season's end.

A challenging campaign for a talented Dortmund squad is ending on a high, with their 4-1 DFB-Pokal final win over RB Leipzig on Thursday followed by Sunday's 3-1 Bundesliga victory at Mainz.

That result means Dortmund, who sit third with one round of games remaining, are certain to finish in the top four. Bellingham piled praise on interim head coach Edin Terzic, who replaced the sacked Lucien Favre in December, for getting the team to tick over the closing weeks of the campaign, having looked doubtful at one stage to earn a Champions League spot.

"I'm very happy," said Bellingham. "I knew what the club's expectations were. We fell a bit short throughout the season, especially in the league.

"We were in the quarter-finals of the Champions League and won the cup. Today we've qualified for the Champions League again after being in a difficult position. That's fantastic, I'm very happy."

Bellingham added, quoted on Dortmund's official website: "Edin has a brilliant personality. He got the best out of us players, wanted to make everyone better. He's done a great job with his team. We are very happy to have him."

Goals from Raphael Guerreiro and Marco Reus in the first half at Mainz were both teed up by Sancho, helping Dortmund on their way to a seventh successive win.

In the process, winger Sancho became the first Englishman from any of Europe's top five championships to reach 10 assists in three consecutive league campaigns since Beckham, who strung together four such seasons from 1997-98 to 2000-01 with Manchester United.

Sancho missed a chunk of this season due to a muscle injury and has made just 25 Bundesliga appearances in 2020-21, but the 21-year-old has still managed 11 assists and eight goals.

Last season he managed 16 assists and 17 goals, while in 2018-19 the teenage Sancho totted up 14 assists and 12 goals.

Sancho – a rumoured Manchester United and Liverpool target – has enjoyed a remarkable week, becoming the first Englishman to score in the DFB-Pokal final as he netted twice in the thumping win over Leipzig.

He tweeted on Sunday that it was "objective complete" for Dortmund as they followed up the silverware with a place at Europe's top table next term, a result that may make it easier for the club to keep the likes of Sancho and Erling Haaland, two of Europe's most coveted young players.