Paul Merson believes Liverpool's bid for a top four finish in the Premier League this season could be undermined by their blunt attack.

Despite currently boasting the best defence in the Premier League this season, Liverpool have only been able to muster 20 goals, a figure that unlikely to improve if Luis Suarez's absence is enforced, and the aforementioned former Arsenal midfield suggests it could play a huge factor come the end of the season.

Liverpool's record signing Andy Carroll has toiled under the weight of expectation at Anfield following his £35 million move in January, and the aforementioned Suarez is likely to face an extended spell on the sidelines because of his pending FA ban. While Liverpool still have the likes of Craig Bellamy, Merson intimates they must start scoring more goals soon.

Liverpool are currently in sixth place, three points behind fourth placed Chelsea, and although the aforementioned Arsenal legend has concerns about the Reds' ability to score goals, he has backed Kenny Dalglish's side to beat Blackburn at Anfield on Boxing Day.

"Liverpool's Achilles heel is putting the ball in the net and you aren't going to get in the top four if you don't do that." Merson told

"But Liverpool should rip Blackburn apart. The away side will play Yakubu up front on his own and it will only be a matter of time before Liverpool score. To be fair, Blackburn have been unlucky in a lot of games this season but you can't keep using that as an excuse for not getting results."

Although he cites Liverpool's woes up front as a possible problem in the long run, Merson predicts an easy 3-0 win at Anfield on Monday.