Jurgen Klopp has admitted that Liverpool are open to bolster the squad during the coming "difficult" January transfer window to address the shortage of options in his attack.

The German manager missedPhilippe Coutinho, Daniel Sturridge and long-term absentee Danny Ings during Sunday's 2-2 draw with West Ham as the Reds were unable to find a winner in the second-half of the game. Divock Origi gave Liverpool hopes to secure a comeback victory after netting the equaliser in the 48th minute of the game but Klopp failed to chase another goal, having only young duo Ovie Ejaria and Ben Woodburn at his disposal on the bench.

"If you watch our bench yesterday, very experienced in defence and not in the same way experienced in the offence," Klopp said as quoted by ESPN during his press conference ahead of the Wednesday' trip to Middlesbrough.

"If the situation stays like this then it's clear that we have open eyes for everything. But the winter transfer market is maybe the most difficult one because the players you want, the other clubs doesn't want to give you. It's not about money. The players you don't want, you can have. That's all. We are always looking. Maybe it's a surprise but we always work hard on this part of the business because we need to have an overview about everything. That's what we do, but nothing else."

Liverpool have struggled in the Premier League since Coutinho suffered an ankle injury during the 2-0 victory over Sunderland, suffering a disappointed 4-3 defeat to Bournemouth before being held to the draw by West Ham at Anfield.

Many have singled out goalkeeper Loris Karius and his defence following both setbacks but Klopp believes that the main problems are elsewhere.

"It's a little bit about formation, at this moment we played with three real strikers. I know everybody misses Phil, of course, but the role he played was very often like a central midfielder or a No8 when he came in the middle," Klopp said. "That means when you misplace a pass from there or lose the ball then we already have a formation for counter-press and things like this. Now we have too many players in the first line.

"We still create chances with this but it's, of course, a little bit too risky. That's what we have to adapt now, we know already what we have to work on but that doesn't mean it works immediately in the first second. And then you concede these kind of goals."