Liverpool manager Jurgen Klopp has received a significant injury boost ahead of Thursday's Europa League quarter-final first leg with Atalanta BC, as four players returned to full training on Tuesday.

The Reds host Gian Piero Gasperini's side on the back of an emphatic 11-2 aggregate success over Sparta Prague in the last 16, triumphing 5-1 away before a 6-1 annihilation at Anfield.

Regarded as one of the favourites to go all the way in the Europa League, Liverpool will clash with either Benfica or Marseille in the semi-finals should they see off Atalanta, before a potential final with either Bayer Leverkusen, West Ham United, AC Milan or Roma.

Klopp's side have a couple of domestic wrongs to right on Thursday, though, as their FA Cup hopes - and in turn their quadruple dreams - were dashed in a 4-3 quarter-final loss to Manchester United last month.

The Reds fell short at Old Trafford once again on Sunday afternoon, needing a Mohamed Salah penalty to salvage a point in a 2-2 Premier League draw, leaving them behind Arsenal in the rankings on goal difference.

Trent Alexander-Arnold, Alisson Becker among players to return

Liverpool's injury crisis has eased slightly over the past couple of weeks, but Klopp was still without seven players for the trip to Man United at the weekend, a few of whom may not play again before the season is over.

However, all of Alisson Becker, Trent Alexander-Arnold, Diogo Jota and Stefan Bajcetic were back in full training with the Merseyside giants on Tuesday, handing Klopp a quadruple injury boost ahead of the run-in.

Alexander-Arnold and Jota have not been seen since sustaining knee injuries two months, the former hurting himself against Burnley on February 10 before Jota came off against Brentford seven days later.

Meanwhile, Alisson was absent from the clash with the Clarets due to illness, and the Brazilian then sustained a severe hamstring issue, allowing Caoimhin Kelleher an extended run in the first team.

Finally, teenage midfielder Bajcetic has only played twice this season due to a combination of groin and calf issues, although the 19-year-old has been training with the Under-21s pain-free and has now been given the green light to practice with the seniors.

Long-term trio still missing for Liverpool

Klopp told the press before the draw with Man United that all four would likely take part in some form of team training this week, but it remains to be seen if any are risked for the first leg of the Reds' quarter-final.

The Liverpool boss will be expected to provide an in-depth update when he faces the media again on Wednesday, but he will still be without three infirm players whose seasons could very well be over.

Joel Matip and Ben Doak are both on the mend from serious knee problems, and the former's ACL issue could spell the end of his Liverpool career, as his contract expires at the end of the season.

Thiago Alcantara is in the exact same boat, having waited 10 months for a first-team return after a hip injury before suffering a potentially campaign-ending muscular problem during a brief cameo against Arsenal on February 4.

Liverpool's only previous home game against Atalanta in the 2020-21 Champions League group stage saw Klopp's men suffer a 2-0 defeat, but they destroyed La Dea 5-0 in Italy that same year.