Inter meet Barca in the Champions League semifinals after seeing off Bayern Munich this week.
And Capello believes Inter have the players and coach, Simone Inzaghi, capable of beating the Catalans.
He told La Gazzetta dello Sport: "(Hansi) Flick's team has great quality, important individuals and plays a less Spanish style of football than in the past.
"The German coach, in fact, loves verticality more than ball possession at all costs and demands from his players a suffocating pressing. When they lose the ball, Barça immediately bites your ankles to win it back.
"It is their strength, but paradoxically also the origin of their fragility."
How you stop this Barca
"The secret," continues Capello, "is to overcome the pressure line: there will be spaces and Lautaro (Martinez) and (Marcus) Thuram will have to be good at exploiting them.
"Not only that, avoiding letting Barça recover the ball immediately would also limit the danger of the three phenomena up front, (Lamine) Yamal, (Robert) Lewandowski and Raphinha. The Nerazzurri also have a weapon that can hurt the Blaugrana: set pieces."
Yamal isn't Messi
On Barcelona's attack , Capello commented: "To stop them, extreme application and attention will be needed. But if the Treble-winning Inter team managed to do it against (Lionel) Messi, they can do it today with Yamal.
"I read some rather risky comparisons about Lamine: he has the talent of a future Ballon d'Or winner and they tell me he's also very humble, but Leo was already unique at 16 and I can confirm this having seen him up close at the time."
Finally, Capello also sees the possibility of playing the return match at the Meazza as an extra weapon for the Nerazzurri.
He stated: "I believe Inzaghi's men can approach the first match away from home better in terms of attention and mental freedom. And then count on the push from San Siro in the 90 minutes that are decisive for qualification."