The 23-year-old took his tally to 13 goals in only 18 games since early December when he returned to action after an injury saga which lasted nearly one year.
Champions Juventus, who host Livorno on Monday and are also involved in the Europa League, have started looking tired and vulnerable while Roma are getting stronger all the time after six wins on the trot.
Destro, who has not looked back since scoring after only eight minutes of his comeback match on Dec. 8, put Roma ahead in the 32nd minute when he tapped in Gervinho's pass from close range.
Radja Nainggolan sent him clear to add the second with a confident finish in the 56th minute and he completed an excellent afternoon by side-footing home an excellent pass by Alessandro Florenzi.
Chile forward Mauricio Pinilla reduced the arrears with a late penalty for Cagliari who were again forced to play in an almost empty stadium because of ongoing rebuilding work at the Sant'Elia stadium. Only around 5,000 fans were allowed in and were packed into a small area behind one of the goals.
Juventus have 81 points from 31 games, with Roma on 76 from 32 and third-placed Napoli on 64 after they lost 1-0 at Parma with a lacklustre display which could not have been more different to the previous week's passionate win over Juventus.
Napoli, who have been exasperatingly inconsistent all season, were sunk by a powerful Marco Parolo strike early in the second half.
Parma moved up to joint fifth with Inter Milan on 50 points leaving the 2010 treble winners in danger of missing out on European football for a second successive season. The fourth and fifth-placed sides qualify for the Europa League.
Torino striker Ciro Immobile scored his 18th goal of the season, pulling him level with topscorer Carlos Tevez of Juventus, to give his side a 2-1 win at bottom club Catania.
Gonzalo Bergessio gave Catania the lead in the second minute and midtable Torino left it late before Alexander Farnerud levelled in the 79th minute and Immobile scored with a deflected goal four minutes later.
Relegation-threatened Sassuolo gave themselves a boost when Nicola Sansone scored twice in a 2-0 win at Atalanta who had set a club record by winning their previous six games.
The teams in the relegation zone are Livorno (25), Sassuolo (24) and Catania (20) while Bologna and Chievo are just outside with 27 each.
Bruno Fernandes pulled one back for Udinese with what appeared to be an intended cross.
Lazio comfortably overcame Sampdoria 2-0 with goals from Antonio Candreva and Senad Lulic despite having Lucas Biglia sent off just before the hour for a second bookable offence.
Lazio lost Germany striker Miroslav Klose to a thigh injury before kickoff while Sampdoria coach Sinisa Mihajlovic was forced to watch his team's meek performance from the stands as he began a two-game touchline ban.
- Sports & Recreation
- Europa League