Having qualified for the Champions League in May, Liverpool's next challenge is to win their first major trophy under Jurgen Klopp, but whether they are equipped to fulfil that aim is the source of much debate at Anfield.

Many Liverpool fans are worried their club have done relatively little in the transfer market, signing only three players, and so far failing to land their two most significant targets -- RB Leipzig midfielder Naby Keita and Southampton defender Virgil van Dijk.

Van Dijk may yet join Liverpool, having submitted a transfer request on Monday, but the club have acknowledged they will not be signing Keita in this transfer window.

The gloomier elements of Liverpool's support have hardly been cheered by the pre-season thigh injury that will keep England midfielder Adam Lallana out until November.

Yet there are grounds for optimism too as Klopp's side begin their Premier League season at Watford on Saturday.

Only the top three scored more Premier League goals than Liverpool last season, and that attack has been strengthened by the club record £37 million ($48 million) signing of Mohamed Salah, one of Serie A's outstanding performers with Roma last season.

Scotland international Andy Robertson, acquired from Hull for £8 million, may be the answer to Liverpool's problems at left-back, while young striker Dominic Solanke arrives from Chelsea with glowing reports of his potential.

Keeping Philippe Coutinho in the face of intense interest from Barcelona would be another significant statement of intent. 

Liverpool have rejected two bids from Barca for the Brazil forward, the second a reported £90 million offer on Wednesday, and have made clear they have no intention of selling a player who agreed a five-year contract last January.

Unfortunately for Klopp, Coutinho may be absent at Vicarage Road, having missed last weekend's friendly against Athletic Bilbao with a back injury.

- Raring to go -

Reds captain Jordan Henderson, who missed the final three months of last season with a foot injury, is fully fit again, and should play after recovering from a virus.

Liverpool had a good pre-season, losing only one of eight games -– and that on penalties to Atletico Madrid -– while recording an impressive 3-0 victory over Bayern Munich at the Allianz Arena.

August will be a key month for Liverpool, as they face Arsenal in the Premier League as well as a two-legged Champions League qualifier against Hoffenheim, but Klopp is raring to go.

"When we finished last season in fourth position everyone was really happy about it," he said.

"Everyone is thinking about the Champions League qualifier but Watford is the first target."

Watford have confirmed Troy Deeney will remain as captain, with new boss Marco Silva confirming he does not expect the striker to be sold.

Deeney is unlikely to play against Liverpool despite returning to training following a groin problem but Andre Gray, who arrived from Burnley for £18 million this week, is set for his debut.

Gray's signing could have cast further doubt over Deeney's future but, asked if he would stay, Silva said: "Of course, he's our player and our captain and he's one player we hope to keep.

"Am I confident? Of course. He's important to us and is our captain and I want to keep him with the team.

"He's our captain. Until now I don't have reason to change nothing.

"Andre's a different player to Troy and Stefano Okaka. They have different types of games. He gives a different option."

Source: AFP