The former Reds midfielder says it feels like he is playing ahead as he waits for the club's second leg against Borussia Dortmund.
The Reds secured a valuable 1-1 away draw in the first leg at Signal Iduna Park thanks to Divock Origi's goal, meaning that they have a slender advantage coming into the concluding part of the tie at Anfield.
However, Dortmund have lost just three times all season in the German Bundesliga and knocked out Premier League title chasers Tottenham Hotspur in the previous round of the European competition, and Jurgen Klopp's side will know they still have a great deal of work to do to progress.
If Liverpool can beat Dortmund or hold them to a goalless draw, they will progress to their first European semi-final in eight years since they lost 4-3 on aggregate to Chelsea in the last four of the 2008 Champions League.
McAteer, who works as a pundit after a playing career which included making 139 appearances for the Merseyside club, was clearly feeling the nerves ahead of the deciding match.
Just had my afternoon kip now for my pre match. Feel like I'm playing again. Nervous but can't wait. Coommme on you red men— Jason MCATEER (@MCATEER4) April 14, 2016
He tweeted: "Just had my afternoon kip, now for my pre-match. Feel like I'm playing again. Nervous but can't wait. Coommme on you red men."
If Liverpool can see off Dortmund to progress to the last four, it would be a huge statement of the club's intent under Klopp after a relatively disappointing league campaign and defeat in the Capital One Cup final to Manchester City earlier this year.
The German manager stated that he believes his former club will now respect the Reds more after their impressive performance in the first leg showed Dortmund that they are in the competition to win it.