The Argentine believes his side will still be able to compete this season and have the infrastructure in place to succeed
The likes of Diego Costa and Filipe Luis, key cogs in the capital club's title success last season, have been sold to Chelsea, while Thibaut Courtois has returned to Stamford Bridge after a loan spell.
However, the Spanish champions have signed Mario Mandzukic and Antoine Griezmann and Simeone feels they will still be capable of challenging.
"We're working from top to bottom," he said at a press conference.
"Now we will return to Madrid and find another group and we'll slowly prepare for the start of the season.
"Today we have the same structure we have had for three years. Obviously our attacking potential made us grow, but the structure is the most important and ours is solid."