I think maybe you mean the fight for 4th place because Atalanta, Lazio, Fiorentina and even Bologna, As Roma and Napoli still have a small difference so they can fight for 4th place, but getting 3rd place is very far away, let alone catching up. Inter Milan and Juventus are at the top of the standings, AC Milan has really maintained their consistency so far as well as Juventus and Intermilan are unbeaten in their last five matches, that is a good job for a very consistent club.
So far there are almost 6 clubs that are likely to be in 4th position at the end of the season, if Atalanta cannot be consistent then they will be easily replaced by the clubs below them, therefore the competition this season is also very tight besides the title competition at the top of the standings is also very tight in the fight for place in 4th position, talking about champions this season, it seems that the meeting between Inter Milan and Juventus in February will determine who deserves to be champion and fight for the Italian Serie A title this season.

Fourth spot in league table is surely going to be the toughest place to fight in coming days because we have six teams which are giving their best for this spot with Lazio, Atlanta and Fiorentina are in better shape because these teams are increasing their performance and consistency with other three are losing points which are surely going to hurt them in coming weeks in last five weeks we have impressive run from Atlanta and Lazio with all four others were down badly which are not ideal but now in coming week we will have Atlanta vs Lazio which will give some advantage to Fiorentina.
But, now it's time for these teams to prepare themselves for the challenge and try to have better results because we already in February and just few weeks left in this season which will be decisive and without preparation things can go on wrong way which could be terrible for them.
In the Italian Serie A table, fourth placed Atalanta and seventh placed Bologna is separated by just three points and that's why I agree to your opinion that the fight for who finishes in the fourth position of the Italian Serie A table at the end of the season is gonna be very tough. Atalanta who are currently in the fourth position will definitely want to maintain their position or even go further to third as the first and second position is far from them at the moment while fifth placed Fiorentina, sixth placed Lazio and seventh placed Bologna are fighting to make sure they make it to the top four. In my own opinion, I think Atalanta will finish in the top four ahead of the other teams in the league.
Left one games for matchday 22 of 38 between Salernitana vs AS Roma, become second matches for new manager Daniele De Rossi for AS Roma after winning debut match against Hellas Verona will be opportunity for him continues three points achievement or he losses on second match. Looking on current standings position, AS Roma has opportunity to return 5th standings position if can secure three points against Salernita behind Fiorentina on 5th position has 34 points.
Serie A have quit well competitive outside top fourth standings position behind Fiorentina, Lazio, Bologna, Napoli and AS Roma remaining fewest points left, interested waiting until the last games of Serie A who will fill the Europe league spot standings and which one team have drop to Conference League spot place.
The Italian Serie A game between Salernitana and AS Roma tonight is going to be an interesting game especially to the fans of the away team team because they're still trying to move up in the league table as well as see their young manager Daniele De Rossi who was recently appointed after the club sacked Portuguese manager Jose Mourinho to succeed at the club. The home side will also go gunning for a win in that game but I think Roma are going to pick up all three points from that game.