The defender says that the Gunners must attack "no matter what" despite knowing they cannot afford to concede in Wednesday's second leg at the Nou Camp.
Arsenal defender Per Mertesacker has admitted that the club cannot afford to concede in their Champions League second leg against Barcelona, but told the Evening Standard that the visitors will go to the Nou Camp to attack "no matter what".
The Gunners conceded twice to Lionel Messi late on in the first leg of their last-16 tie against the Spanish giants at the Emirates Stadium last month to leave them on the brink of elimination at the first knockout stage.
Mertesacker says his side cannot afford to concede a goal in the second leg which would leave them needing three to advance, but admits they will have to attack the hosts as they look for two goals without reply to take the tie to extra time.
The German centre-back, who admitted that the North London side simply have not scored enough goals this season, told the Standard: "We cannot afford to concede [but] we have to go there and try to attack, no matter what.
"That is the only possibility we have. We can be fortunate to have such big game in front of us but I cannot predict, it is really hard.
"Barcelona is the ultimate team at the minute, so we are straight away under pressure. But the confidence is there, we are just missing something."
Arsenal are enduring a torrid run of form which has seen them go from competing on three frontiers to the verge of having something of a dead season on their hands.
The Gunners have won just four of their last 14 matches in all competitions and only one of their seven since Valentine's Day, and are now eight points off the pace in the Premier League ahead of Leicester City's clash with Newcastle United on Monday night.