The Wales international has fallen out of favour in recent months after Lucas Leiva’s return from injury and Jordan Henderson’s impressive performances.
And the £15m signing is desperate to rediscover his old Swansea form after a difficult start to his Liverpool career.
“My form hasn’t been great, especially compared to the start of the season, but that is more down to myself,” said Allen.
“But I am looking forward to working hard and try to turn things around a little bit.
“I haven’t played that much recently so any chance I get to participate then I’ll be hoping to impress as much as I can and stake my claim.
“We were bitterly disappointed after Monday’s defeat to West Brom, that goes without saying, but we have this tie to look forward to and refocus.”
• Zenit have played five games against English opposition – most recently winning the 2008 Super Cup via a2-1 victory against Manchester United in Monaco – with the record W3 D0 L2.
• Zenit have been to the city of Liverpool before, losing 1-0 against Everton in the 2007-08 Uefa Cup group stage. They went on to win the competition that season, though.
• Liverpool have already met a Premier-Liga side this season, winning 1-0 at home and losing 1-0 away against Anzhi Makhachkala in the group stage.
• The Reds’ record in nine games against Russian clubs (including a 3-1 win against CSKA Moskva in the 2005 Super Cup in Monaco) reads W5 D1 L3.
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