Jürgen Klopp believes Liverpool are hitting their stride again, as a convincing 3-1 win against West Ham was accompanied by the news the club are finally preparing to sign a centre-back.

The Premier League champions have agreed a £2m fee with Preston for their 25-year-old defender Ben Davies, with the academy prospect Sepp van den Berg going in the opposite direction on loan.

The arrival of Davies would ease some of the pressure on Liverpool’s injury-ravaged backline, with Klopp forced to name Jordan Henderson and Nat Phillips – his 12th centre-back partnership in the league this season – at West Ham. Davies had been in talks with Celtic over a pre-contract agreement to join in the summer and was a target for Burnley.

After Liverpool registered a second successive London win, following the victory against Tottenham on Thursday, Klopp said the club’s poor run of form had led to some difficult conversations in the squad, as well as a number of tactical tweaks that have made Liverpool “uncomfortable” opponents again.

“We spoke a lot in the last few weeks, as you can imagine,” he said. “These boys are a really good group. They are not happy with not being successful. They always have the right attitude. But they need the right information as well. Now we have a found a way again to be uncomfortable for other teams.”

On the move for Davies, who has spent his whole career at Preston other than loan spells, Klopp remained tight-lipped. “On transfer things, we don’t say anything until something is done. I’ve said it all the time: in our situation, it makes sense [to sign a centre-half]. Our eyes are always open and we try to fix our situation if we can do it. If not, we play like we did tonight.”

Mohamed Salah made a thunderous return to form with two fine goals, the second a cheeky finish after a thrilling length-of-the-field counterattack, and he said Liverpool would need to win every game to challenge the leaders Manchester City, who they trail by four points having played a game more.

“City were struggling in the beginning, then we were struggling three or four games ago,” he said. “Now we need to keep winning if we want to win the league. It’s been a really big week.”

The West Ham manager, David Moyes, lamented his team’s lack of composure on the ball. “We didn’t get the ball down and play,” he said. “But there are three or four teams in the Premier League who are better than all the rest, and Liverpool are among them. We’ve got a long way to go.”