Three-time European Cup winner Brian O'Driscoll believes this season's European Rugby Champions Cup will be more difficult to win than ever.
The 38-year-old, now a pundit, lifted the European Cup with Leinster Rugby in 2009, 2011 and 2012, but insists it's a harder trophy to win now.
"I think it's tougher to win these days than when I was involved," O'Driscoll told BT Sport.
"If you just look at the calibre of the Pools, there's very few sides that you think wouldn't get a victory.
"I feel fortunate that I was involved in three winning sides when it was a lot easier than it is now."
The former Ireland centre reckons the 2017-18 competition could have the same finalists as last year, if they both progress from a tricky Pool 2.
"I think Clermont and Saracens will be in the mix again, Leinster will be there and Munster won't be a million miles away," he said.
"And Toulon will be there again. They have the experience and a wealth of players who know how to get out of any Pool."
O'Driscoll, who made 133 appearances for Ireland and eight for the British and Irish Lions, felt his first European Cup win in 2009 was the greatest achievement of his career.
"The first time you lift it has to be the most special," he said.
"After 10 years of disappointment it was great to go and win it against one of Europe's big names in Leicester Tigers, having beaten Munster in the semi-final.
"The second and third were the icing on the cake, but that first one was very special because it was a relief."