The midfielder was frustrated by his side's failure to turn their dominance into goals against the Rossoblu but says the Giallorossi are still on course for the Champions League
After kicking off their campaign with 10 successive victories, the Giallorossi had been hoping to get back to winning ways after being held by both Torino and Sassuolo in their two previous outings.
However, a combination of poor finishing and sensational goalkeeping from Vlada Avramov meant Roma were forced to settle for a point for the third consecutive game, much to De Rossi's frustration.
"We're disappointed because we have created so many chances but, unfortunately, we didn't take them," the midfielder told Sky Sport Italia.
"We have nothing to complain about, though. We have hit the post and the Cagliari goalkeeper was the best player on the pitch.
"I don't know what you could blame us for, as there was plenty of commitment: we tried right until the end; our shape was always there.
"We still have a seven-point advantage on fourth place. We want to go into the Champions League, although obviously we will try to again take top spot in a championship that remains very positive for us.
"I challenge anyone to say differently."
Roma's draw means that they are now one point behind two-time defending champions Juventus, who went top on Sunday courtesy of a 2-0 win over Livorno.