Jurgen Klopp says Liverpool will go into the new season with an improved squad and there is reason for "real optimism" at the club.

Liverpool returned for preseason training on Wednesday morning and Klopp must ensure his players hit the ground running with a two-legged Champions League qualifier to play soon after the Premier League season begins.

"We all know in a few weeks we have these qualifiers and there will be pressure on the game," he told Liverpool's official website. "But now we have the time to prepare this and we have to use the basis we created last year -- it was not too bad.

"We all know it could have been maybe a little bit better but it could have been much worse.

"We are now one of the top four teams in England so now we want to keep this situation and work with it and improve.

"The squad will be stronger this year than it was last year. That's a real reason for real optimism."

Liverpool are preparing for a big season under Jurgen Klopp. John Powell/Liverpool FC via Getty Images

A number of players including Mohamed Salah, Philippe Coutinho, Adam Lallana, Emre Can, Dejan Lovren, Simon Mignolet and Georginio Wijnaldum will come back later as a result of international commitments.

But with their first preseason friendlies just a week away the focus is on getting the current group ready for action.

"I saw the boys this morning and I saw in their faces that they're ready to go. So I'm ready to go,'' Klopp added. "Of course, it's not what they love most, it's kind of a weird relationship [with preseason] -- you don't want to do it but you know it's necessary so you do it. You feel bad before and you feel perfect afterwards.

"It's important for us to know from which point we can pick them in the next few weeks. They all look pretty much in a good shape."

Defender Joe Gomez is one of those back in for training and he is looking to make up for lost time after missing almost two seasons, playing just three first-team matches in January after recovering from a serious knee injury.

"Obviously you have bits when you're anxious about the running, because it's going to be difficult," the 20-year-old said. "I've had a lot of tough periods and stuff but I'm just grateful to be here and happy to go again.

"I'm 100 percent. I feel good, I feel fit, sharp, I'm in a good place mentally and physically. I just see it as a fresh start now to go again and attack this season."

One youngster who will be missing preseason is Rhian Brewster, whose rapid progress last season saw him promoted from the under-18s through the U23s to a place in Klopp's squad, as he is likely to be out for eight weeks with a broken foot.