The England right-back, 24, becomes manager Rafael Benitez's first signing of the summer as he seeks to build a squad capable of going one better than last season's second-place finish in the Barclays Premier League.

Benitez told the official club website: "We were thinking about bringing in players with quality - that's the first thing. He is also English and that is important for the Champions League list. We were thinking about improving the team and Johnson is a very good player who will do that.

"He was important at Chelsea and in the last year at Portsmouth he has improved and is much better. One of the main things is his mentality - it's really good. He is a winner. I was impressed with the conversations I had with him. He wants to improve.

"We knew the market was going to be difficult this summer and some of it has been crazy. Manchester City and Chelsea were there - they were making offers. We had to be quick and the club acted quickly.

"It was down to the player whether he chose us or City or Chelsea and he chose us. It was very clear from talking to him that he wanted to play for Liverpool.

"We are working and trying to bring new players in but we are happy with the squad we have at the moment. We were thinking about improving and with Johnson we have improved. Like I have already said, we could buy one more player without selling anyone. We now have to wait."

massive hit

Johnson's career began with Harry Redknapp at West Ham United but after just 15 appearances and a loan spell at Millwall he became the first signing for new Chelsea owner Roman Abramovich in 2003.

The Londoner's league debut for the Blues came at Anfield against Liverpool in August of the same year.

Three months later he made his international debut against Denmark as a substitute for Gary Neville.

Johnson won a Premier League title winner's medal and a League Cup during his time at Stamford Bridge but he was loaned to Portsmouth by Jose Mourinho in 2006.

The deal was made permanent a year later and the England man went on to be a massive hit with the Fratton Park faithful.

He helped the club win the FA Cup in 2008 - and the season that followed brought a host of personal accolades.

Despite Pompey finishing 14th in the league, Johnson was selected at right-back in the PFA Team of the Year for 2008-09. His screaming left-foot volley against Hull City on 22nd November also won Match of the Day's Goal of the Season.

The defender has amassed 15 caps for England and was named as Nationwide's man-of-the-match in the Three Lions' recent World Cup qualifying victory over Andorra at Wembley after claiming three assists in the match.

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