The Real Madrid captain has won four Champions Leagues with the club, but his five LaLiga Santander titles are just half of that won by Messi with the Catalans.
"We've suffered against Messi during these years," Ramos said in his documentary series 'The Legend of Sergio Ramos'.
"Perhaps if Barcelona didn't have him, we would have won more titles.
"There was a time when we faced the best Barcelona in history. We had a great coach like [Jose] Mourinho, but it was hard for us to beat them.
"We didn't win much and there was a lot of tension, caused by either them or by us."