Serbian winger Adem Ljajic struck twice, including an injury-time equaliser, to rescue 10-man Roma in a stunning 2-2 draw with Sassuolo that threatened to derail the Giallorossi's title hopes on Saturday.
Roma had conceded their first league goals of the season at the Olimpico in a 4-2 win over Inter last week.
But only four days before hosting Manchester City in a must-win Champions League clash, Sassuolo's unforgiving front line sorely exposed Roma's defensive weaknesses.
Despite spurning the chance to close to within a point of leaders Juventus, Roma coach Rudi Garcia was thankful of the point having lost midfielder Daniele De Rossi after his sending-off in the 52nd minute.
"We showed our grit. Tonight's game was yet another test. Down 2-0 and losing a man means we've done exceptionally well tonight," Garcia told Sky Sport.
"We had 24 shots, although we should have had more on target and with 10 men that shows you how strong we've stayed in attack."
Roma's setback means they are now three points behind champions Juventus following their scoreless draw at Fiorentina on Friday, but Garcia said: "You can't get them (points) back, they've gone."
With one eye on the Champions League Group E clash with City, Garcia rested Francesco Totti and Radja Nainggolan, while left-back Ashley Cole sat out the second game in succession.
A combination of injury and illness meant Roma were also without Vasilis Torosidis and Leandro Castan, with midfielder Alessandro Florenzi forced into filling in at right-back.
- Zaza brace -
Garcia's defensive woes were made apparent within 18 minutes when Italy striker Simone Zaza pounced twice to give Sassuolo a shock 2-0 lead.
Zaza broke the deadlock on the quarter-hour after chasing down a Mapou Yanga-Mbiwa backpass to Morgan De Sanctis.
The Roma 'keeper tried to clear but as he did so Zaza slid in to block and the ball bounced into the back of the net.
Incredibly, Roma were trailing 2-0 three minutes later when their offside trap collapsed.
Zaza, in possession, coolly strode towards goal unhindered to fire past a flailing De Sanctis and into the roof of the net from just outside the box.
The last time Roma had conceded two goals before half-time at home in Serie A was against AC Milan on October 29, 2011, although Garcia's men conceded five before half-time in October on their way to a 7-1 Champions League drubbing at the hands of Bayern Munich.
A stunned Roma went about fixing the damage, but promising efforts by Mattia Destro and Ljajic missed the target, while minutes before half-time only a timely intervention from Jose Holebas stopped Domenico Berardi from tapping in from close range.
De Rossi saw red for a second bookable offence after he pulled down Berardi as the winger broke clear only seven minutes after the restart.
Kevin Strootman, making his first league start at the Olimpico following his recent return from injury, and Juan Iturbe made way for Nainggolan and Gervinho respectively on 54 minutes.
But despite their arrival, Roma looked far from safety -- De Sanctis had to get down smartly to his right moments later to parry a low curling shot from Berardi with one hand.
However, Roma won a lifeline when Gervinho's shot struck the hand of defender Sime Vrsaljko on 78 minutes and Ljajic stepped up to roll the resulting penalty down the middle past Andrea Consigli.
The Serbian struck again in the third minute of added-on time when Gervinho's ball fell to Florenzi on the right just outside the area and Ljajic whipped the Italian's cutback into the net.
Zaza was proud of taking his season goals tally to four, but with his side missing the chance to jump up to sixth place, he told Sky Sport Italia: "There's a lot of bitterness because we thought we'd be taking a result home with us. But for how Roma levelled, there's also some anger."
In Saturday's late game Argentinian striker Paulo Dybala scored for Palermo in a 2-2 draw at Torino, for whom defender Kamil Glik rescued a point in the 63rd minute.
Palermo leapfrogged Inter into 11th place before the Nerazzurri's home game with Udinese on Sunday.
Source: AFP