The Merseyside outfit finished in fourth place in the Premier League table to secure a place in the Champions League for the second successive season.
Liverpool FC still finished 25 points behind Premier League champions Manchester City in the table this season to highlight the gap between the two clubs.
However, the 18-time English champions were the first team to beat Manchester City in this season’s Premier League after a 4-3 win at Anfield.
Liverpool FC secured a 3-0 lead in the first leg of their Champions League quarter-final before beating Manchester City 2-1 in the return leg at The Etihad.
The Merseyside club will take on La Liga giants Real Madrid in the Champions League final in Kiev as Jurgen Klopp looks to win his first trophy.
Former Real Madrid midfielder Alonso believes the Reds need to underline their progress under Klopp with a Premier League title challenge next season.
“It’s unbelievable, what they have achieved. And not just their result of reaching the final, the way they have been able to build an idea of how they want to play,” Alonso is quoted as saying by the Daily Mirror.
“From this strong base, now they have to continue building, adapting and improving. I think that’s very important, that they have in this moment this idea about the team, about how they want to play.
“The next step is not securing top four, it is challenging for the title and that’s the big one that probably is the most difficult one.
“We know Liverpool, they can beat anyone, but they need to find that consistency to be regular in the whole season. We were close and we didn’t make it – hopefully they can make it.”
The Reds haven’t won the Premier League title but finished in second place in 2002, 2009 and 2014.
Liverpool FC finished in fourth place in the Premier League last term to ensure their continued participation in the Champions League.
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