Starting both England games during the international break, Lallana completed 66 minutes against Germany followed by the full 90 minutes on Sunday, providing an assist for Jamie Vardy's goal in the home win against Lithuania.
However, on returning to Liverpool to rejoin the squad in preparation for the Merseyside derby against Everton on Saturday, scans have revealed the midfielder has suffered a thigh injury that will rule him out for approximately a month.
Huge blow for Liverpool
Lallana's absence will be a huge blow for Liverpool's top-four hopes as we enter the business end of the season.
The midfielder has been in terrific form this season for both club and country, with three goals and an assist in his last five appearances for England to go alongside seven goals and seven assists in the Premier League this campaign.
The 28-year-old has established himself as a key member of Jürgen Klopp's side, providing energy and guile from the midfield to help support the forward three of Philippe Coutinho, Roberto Firmino and Sadio Mané.
His absence, along with other key members of the squad, will put real pressure on Liverpool and their hopes of securing Champions League football for next year.
A change of formation?
The Brazilian has struggled since returning from his injury in January but could thrive in a more withdrawn role, much like Lallana has done this season.
That would allow Divock Origi to come into the side and add some extra pace to the front three alongside Mané. The Belgian has experienced a poor campaign in truth, but Lallana's injury could offer him a great chance to turn things around - and what a time to do it.
However, if Jordan Henderson manages to prove his fitness before the weekend, it is likely he will slot straight into the midfield in place of his international teammate. This would see him or Wijnaldum provided with a greater licence to roam forward, with Can keeping his spot in the number six role.
Lallana's injury has come at the worst possible time for Liverpool, who would have wanted to take some momentum into the Merseyside derby after a solid draw against Manchester City and wins against Arsenal and Burnley.
It's a huge blow to their rhythm, but the Reds mustn't let it derail their season when they are so close to bringing European football back to Anfield.