The Uruguayan forward teamed up with Daniel Sturridge in attack last season and the prolific duo almost fired Liverpool to the Premier League title.
However, Suarez joined Barcelona last summer and, with Sturridge struggling with injuries, the Reds made a stuttering start to the current season.
However, they have been in fine form since December and Sunday???s 2-0 win at Southampton was their seventh success in a 10-game unbeaten run which has taken them to within two points of fourth place.
And Allen says Liverpool may now be even stronger than they were last season.
“At the start of the year we talked about how losing Suarez was going to have an affect but now we have overcome that,” he said.
“It took us a little bit of time to overcome that, because the injury problems we had were not ideal.
“We are certainly back up to that level and, if anything, with the different system we play this season we might even have taken a step forward.???
Allen accepts that the team deserved criticism for some of their displays earlier in the campaign but says they were always confident that better times were on the way.
“I don’t think it was unfair,??? he said. ???There were no hiding places and we were not delivering as players.
“There were no excuses from us. We knew there might be a difficult patch early in the season and that probably went on longer than we hoped and expected.
“At the same time, we always knew we would come through it, and I think that was the biggest sign we would be where we are at this stage.”
As well as being in the thick of the race for a Champions League place, the Reds are through to the FA Cup quarter-finals and will be in Besiktas on Thursday looking to secure a place in the last 16 of the Europa League, having won the first leg 1-0.