Sassuolo may be an obstacle for strong teams like Inter and Juventus this season but that doesn't seem to be the case against Roma. The reason is that Roma managed to beat Sassuolo in the away match with a narrow victory and this allowed Roma to occupy position 4 for the time being. It seems that Roma is aware that they cannot continue to dwell on uncertain results and they have proven this with their consistency so far. Roma's next opponent that is waiting for them is Fiorentina and of course this will be a fairly balanced match for both teams and I am quite curious which of them will win in Week 15.
I can't really say if not for the red card that one of the Sassuolo players received and they remain 10 players against 11 players, I don't think Roma will be able to win the game. The highest performances from Roma I was expecting is just to play draw because Sassuolo was leading with one goal in the first half, and it was till 60+ minutes after Sassuolo received the red card, Roma had chances to score. That shows there is a big probability that if Sassuolo did not receive that red card, Roma may not get good chances to score.
The upcoming match between Roma and Fiorentina is expected to be unpredictable due to the strong play of both teams. However, based on past head-to-head results, Roma has always looked formidable at home against Fiorentina, trying to replicate their style of play when playing the team. It is currently Roma's home game, and based on head-to-head statistics, I believe Roma has a better chance of winning or drawing, but I cannot guarantee Fiorentina will be able to defeat them in the upcoming game.