Brendan Rodgers has underlined the extent of Dejan Lovren’s problems at Liverpool by admitting Kolo Touré was selected ahead of the £20m defender at Arsenal because of his commitment.

The Croatia international has had a difficult start to his Liverpool career having arrived as a key and expensive recruit from Southampton last summer. Lovren was fit for Saturday’s 4-1 defeat at the Emirates Stadium, having missed the recent international break with an abdominal injury, but failed to make the starting lineup in the absence of the suspended Martin Skrtel.

Rodgers favoured Touré against Arsène Wenger’s side only for the 34-year-old to produce an erratic performance on his return to north London. Rodgers defended his decision as he backed Liverpool to respond to their Champions League qualifying setback in Wednesday’s FA Cup quarter-final replay at Blackburn Rovers. The manager claimed Touré merited inclusion over Lovren for the Ivorian’s attitude on a daily basis.

Asked why Lovren, Liverpool’s most expensive defensive signing, did not start on Saturday, Rodgers said: “The thing with Kolo is he gives me everything every single day so I know what I am going to get with him.

“Dejan was obviously out over the international break but now he is fighting well and looking strong. He will be in contention for the Cup game for sure.”

By implication, Rodgers does not yet know “what I am going to get” from Lovren, who has made only 16 Premier League starts this season and returned to the bench following the goalless draw with Blackburn at Anfield on 8 March.

The 25-year-old is not guaranteed to start the replay even with Skrtel and Emre Can suspended as Glen Johnson, out of contract this summer, is vying for inclusion in place of the Germany Under-21 international Can. Assessing Liverpool’s overall transfer record last summer, Rodgers said: “You bring players in with all the intentions of them doing well. What you cannot vouch for is when they come into a club of this size how long that adaptation process is going to take. You’ve seen that over many years at this club.

“You can be a very good player and not hit it off for some reason or it just takes time, like Lucas Leiva. It didn’t quite happen for him early on in his Liverpool career but he ended up doing well and the supporters appreciate the role he plays. It’s just unfortunate because these players need time and you don’t get that in modern football. We had a big influx of players coming in last summer so it was always going to be difficult for them all to hit it off straight away but I think you can see the progress that has been made. It just takes a bit of time.”

Consecutive league defeats to Manchester United and Arsenal have damaged Liverpool’s prospects of qualifying for the Champions League, leaving the FA Cup as a more realistic opportunity to reward a turbulent campaign.

Recent results have also invited questions over Rodgers’ 3-4-2-1 formation, specifically whether opposition teams have found out Liverpool, but the manager insists the system is not at fault. “Our possession just hasn’t been good enough recently, that has been the key to it,” he said.

“We need to build the game quickly but it has been too slow and there is no excuse at The Emirates as the pitch is wonderful. It wasn’t just against Arsenal and Manchester United, it was the same in the first half of the Swansea game. The speed of our game hasn’t quite been there, the speed of our passing.

“Against Man United we gave the ball away too often and there was too much space. The Arsenal game we didn’t start well, we got back into it but then defended poorly. I don’t think it was anything to do with the system, we just didn’t pass the ball quick enough. We also had a number of important players missing on Saturday, we have to remind ourselves of that.”