The Fulham manager admits that his side has missed American attacker Clint Dempsey this season, particularly his ability to score goals against the run of play.
Dempsey - as well as Mousa Dembele - joined Tottenham Hotspur last summer. The U.S. international had led the Cottagers in Premier League scoring for five straight seasons. He scored 23 goals in all competitions in 2011-12.
Berbatov, who finished top scorer in the Premier League in 2010-11, joined from Manchester United. The Bulgarian scored 13 goals this season, including the consolation in a 3-1 loss to Liverpool FC on Sunday.
"Last year we could score out of nothing; we had Clint Dempsey to score winners," Jol told reporters. "With Dimitar Berbatov, we gained somebody who could score goals but we lost things in other areas."
The London club all but avoided relegation by reaching 40 points, but slumped from its ninth-place finish last season.
Fulham has lost six of its last seven games.
"We were very happy to be on 40 points but we haven’t been able to get a result since to be on 46 or 47," the Dutch coach said following the Liverpool loss. "If you look at the effort we’ve put in against Chelsea, Arsenal and even today, there’s nothing wrong with the effort or application or mentality, but when we’ve needed to change the game to score, we’ve looked a bit vulnerable."
The Cottagers' boss believes Fulham has a lot of work to do in the summer to ensure it doesn't tail off again, and feels the the club could need as many as six new players ahead of next season.
"We need four, five or six players but that’s normal at any club,” he said. “We need to strengthen."
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