Stephan El Shaarawy shot Roma to within touching distance of Serie A's Champions League places with the late winner in Sunday's 1-0 success over 10-man Monza.
Italy international El Shaarawy lashed in a low finish in the 90th minute at the Stadio Olimpico in Rome, pushing Jose Mourinho's team up to sixth with their third straight league win.
Roma, who also struck the woodwork late on through Romelu Lukaku and Sardar Azmoun, are three points behind Napoli, Fiorentina and third-placed Juventus who take on AC Milan in the weekend's big match later on Sunday.
El Shaarawy's first goal of the season came at the end of a tough match against 11th-placed Monza who had to play the entire second half with 10 men following Danilo D'Ambrosio's harsh sending off four minutes before halftime.
"When I saw Azmoun's shot, more than Lukaku's, hit the post I thought, bah, if that doesn't go in... but Stephan has a feeling for goals and scoring late so he won the match for us," said Mourinho to Sky Sport.
Mourinho was sent off in stoppage time as tensions flared between the two dugouts after El Shaarawy struck, the Portuguese making a crying motion at the Monza staff.
"The only ones complaining about the referee were them. I'm not criticising them for it but for the fact that after a match like that they had some nasty words for us," added Mourinho.
Defeat for Monza was harsh as the away side put up a brave fight despite being a man down for half the match, El Shaarawy's winner the first goal they have conceded from open play since being thumped by Atalanta the start of September.
Raffaele Palladino's Monza look set for another decent season in Italy's top flight after being promoted last year and weren't fazed by new signing Papu Gomez being hit with a two-year doping ban on Friday.
LATE DRAMA
Gomez's suspension was a huge blow to Monza as the Argentine was brought in to replace star man Gianluca Caprari after he was ruled out for months with a knee ligament injury.
"I saw the boys out there with heart and giving their all. I praised my team after the match because they showed a lot of character," said Palladino.
Roma struggled to break down Monza even after D'Ambrosio was sent off for two bookable offences.
The hosts didn't create a decent chance on goal until the 37th minute when Houssem Auoar headed Andrea Belotti's cross straight at Monza goalkeeper Michele Di Gregorio from point blank range.
And on the stroke of halftime Di Gregorio again kept Roma at bay, this time kicking away Belotti's clumsy finish from Leonardo Spinazzola's cross.
Monza responded to D'Ambrosio's red card by sitting back but it was the away side who went closest with two well-struck distance efforts from Andrea Colpani and Samuele Birindelli, the second of which was well stopped by Rui Patricio.
Lukaku had a quiet day and was unlucky in the 73rd minute when he struck the outside post, but Birindelli was denied again moments later by Patricio at the end of a rapid counter-attack.
Azmoun then wasted a glorious opportunity to snatch the win with two minutes remaining when he thwacked the inside of the post following strong hold up play from Lukaku.
But with the match seemingly over El Shaarawy pounced after another Azmoun shot was blocked, sparking wild celebrations in the stands.
Bologna are nestled behind Roma on goal difference after beating promoted Frosinone 2-1 while Filippo Inzaghi's new team Salernitana and Cagliari drew 2-2 a frantic match between two struggling sides.
Boulaye Dia salvaged a point from the penalty spot in the fifth minute of stoppage time after his 86th-minute leveller was cancelled out just two minutes later by Nicolas Viola.
Dia's first goals since August left Cagliari bottom of the division, one point below Salernitana and Empoli who take on Fiorentina on Monday night.