Jamie Carragher believes Liverpool's 2025 summer transfer window could go down as "arguably the worst" in Premier League history.

The Reds spent big in the window last summer as they looked to build on their Premier League triumph under Arne Slot, who was eventually sacked at the end of last season.

Liverpool broke the British transfer record twice in the summer of 2025, first for Florian Wirtz (£116m/ €135.6m) and then for Alexander Isak (£125m), while also signing Hugo Ekitike, Milos Kerkez, Jeremie Frimpong, Giovanni Leoni and Armin Pecsi.

Overall, Liverpool spent a reported £450m to bring those players to Anfield, but the majority of them have struggled so far on Merseyside.

Isak directly contributed to just five goals (four goals, one assist) in 22 appearances as he struggled with fitness before suffering a broken leg, while Wirtz scored seven goals and provided eight assists in 49 appearances.

Ekitike, however, did thrive under Slot, netting 17 times and recording six assists in 45 games before suffering an anterior cruciate ligament (ACL) injury in April.

Liverpool started their 2026-27 campaign with a 2-2 draw at Newcastle United, and Carragher claimed their 2025 summer signings must start performing better.

"It's the first game of the season, but my fear is this window of 12 months ago could set Liverpool back a year or two, to fix it," the former Reds defender said on Sky Sports.

2 - Liverpool conceded two fast break goals in a Premier League game for the first time since MD1 last season (v Iraola's Bournemouth).

This is as many as all other teams combined (2) in the opening round of this season's PL games so far.

Open. pic.twitter.com/LUNvK8lCzM

— OptaJoe (@OptaJoe) August 23, 2026

"Yes, it's one game under Iraola, but we're talking 12 months of underperformance from all of these players except [Ekitike].

"If this doesn't change in the next two or three months under Iraola, and these players improving, I think we're going to be looking at that as arguably the worst transfer window we've probably seen in Premier League history, when you consider the fees for these players, and what it's going to do for Liverpool.

"The idea of these players wasn't just coming in and being good players. It was to create almost a little dynasty for Liverpool.

"Let's not forget, Liverpool won the league two years ago. These [players] were supposed to do what City have done over the last few years, or United in the past, where they go and win two or three leagues in five years."