Steven Gerrard remains confident that Liverpool can overcome the odds to progress in the Europa League but was left frustrated at his side's worrying tendency to concede sloppy goals.

Liverpool had plenty of chances to take the lead against Zenit St. Petersburg, with Luis Suarez the main culprit as he failed to hit the target on four occasions, before goals from Hulk and Sergei Semak condemned them to another defeat.

Hulk celebrates as Liverpool players look on in despair [Reuters]

The disappointing result came on the back of Liverpool's continued profligacy in front of goal as they spurned numerous chances against West Brom before succumbing to a shock 2-0 home defeat.

Even when Brendan Rodgers' side had excelled in front of goal in recent weeks when scoring two against Arsenal and Manchester City, defensive mistakes cost them as they ended up drawing both games.

In fact it is now four games in succession that Liverpool have conceded two goals and Gerrard was left rueing the side's lack of concentration in giving away bad goals.

"Up until the 70th minute against Zenit, the game was under control," Gerrard told the official Liverpool website. "We're disappointed with the two sloppy goals we conceded, but the tie is not over.

"It wasn't the result we wanted - we wanted an away goal and to try and sneak away with a clean sheet, but if you concede sloppy goals, you get punished and that's what happened. If anyone can pull it back, it's us."

Veteran Liverpool defender Jamie Carragher also stated his annoyance at the result and refused to blame the forward players for not taking their chances, instead questioning the side's ability to defend as a team.

It's frustrating because up until they scored it was just about a perfect European night for us really," the No.23 told the Liverpool Echo.

"We can't just say we created chances and should have scored," said Carragher. "There's no point us looking at the strikers. We have each got to look at ourselves as a team defensively in that situation.

"The fact is we can't keep conceding goals like that, especially at that stage of the game. We had got to the 70th minute and we were doing well. The first goal is a great strike but you can always defend situations like that better.

"Then the second goal is a poor goal all-round from us and that's something you get punished for at this level. We dealt with the onslaught in the first half. We created a few chances and in the second half we looked in control - that's European football."