Romelu Lukaku and Lorenzo Pellegrini made the most of Paulo Dybala assists to give Roma their second Serie A win of the season and Frosinone’s second defeat.
The Giallorossi were in crisis after one Serie A win in six rounds, coming off a humiliating 4-1 defeat to Genoa. Diego Llorente joined Chris Smalling, Renato Sanches, Tammy Abraham and Marash Kumbulla on the treatment table, so Bryan Cristante dropped into defence. Frosinone were on the other hand unbeaten since the opening weekend, though Kaio Jorge, Pol Lirola, Francesco Gelli and Abdou Harroui were not fully fit.
Stefano Turati struggled with an in-swinging Paulo Dybala corner, while Gianluca Mancini intercepted the Riccardo Marchizza pull-back for Marvin Cuni.
Frosinone threatened to take the lead on 18 minutes when Cuni ran onto a ball over the top, taking it away from both Rui Patricio and Evan Ndicka, but then narrowed the angle too much and was only able to hit the side-netting. The visitors also lost Simone Romagnoli to injury moments later.
Instead, Roma broke the deadlock when Mancini’s through ball was flicked on by Dybala for Lukaku, who with a change of direction sent a defender to ground, freeing up the space to drill in from 12 yards.
Cuni went close again, blasting off target after running onto a Matias Soule ball over the top, while Lukaku stung Turati’s gloves on a Lorenzo Pellegrini counter-attack.
Baez tested Rui Patricio at the near post, while Dybala dribbled down the left to pull back from the by-line and Ilario Monterisi risked an own goal to prevent the Lukaku tap-in.
Turati rushed off his line and used his legs to parry from Edoardo Bove at the near post, but Soule flashed a ball across the six-yard box that nobody was ready to tap in.
Bove fired over from a Dybala lay-off and Pellegrini was about to come off when visibly exhausted, but Mourinho delayed the change until after a free kick.
It was a wise decision, because Dybala floated the set play to the back post where Pellegrini volleyed in with his right boot from the tightest of angles.
The fatigue was getting to everyone including referee Matteo Marchetti, who had to halt play for a few minutes because he too had cramp, leading to nine minutes of stoppages.
Roma 2-0 Frosinone
Lukaku 22 (R), Pellegrini 83 (R)
(Assist: Paulo Dybala)
(Assist: Paulo Dybala)