In the Premier League clash at Old Trafford on March 25, in which City beat United 3-0, a first-half clash between United midfielder Fellaini and Zabaleta left the latter on the ground.
Referee Michael Oliver booked Fellaini for his part in the incident, although TV replays suggested the Belgium international had elbowed the Argentina full-back.
Also, footage later emerged which appeared to show Fellaini spitting near to Zabaleta's head.
The Football Association confirmed at the start of this week that it would take no action in regard to the spitting allegation.
Zabaleta, whose City side plays host to Southampton on Saturday, is still surprised that Fellaini was not sent off by Oliver for the initial challenge, but has no axe to grind over what ensued in the aftermath.
"He (Fellaini) said that I ran into his elbow, but that's the funniest thing I've ever heard in my life," Zabaleta told the Daily Mail.
"I know I'm not the tallest player in the league, but he left the ball and tried to elbow me. He should have been sent off for that, 100 per cent.
"I'm not going to say anything about the spitting because I didn't see it when I was on the pitch. I saw some images after the game, but I will respect the FA's decision."
Zabaleta, who joined City in summer 2008 for £6.45million from Espanyol, has also spoken of the speculation that he might be the man to eventually persuade his international team-mate Lionel Messi to move to the Premier League - and sign for City.
The 29-year-old is close friends with the 26-year-old Barcelona superstar.
"We were joking a little bit about if there's one person to convince Messi to come to England, it's me," added Zabaleta. "But I don't want to put pressure on myself by saying that I'm the man to bring Messi to Manchester.
"Messi is like a god there and I heard he's probably going to sign a new contract. I don't see him leaving Barcelona in the future."
As for his own future and the fight to keep his place under Manuel Pellegrini, Zabaleta adds: "I've been here for six years and always had big competition with different players - Micah (Richards), (Jerome) Boateng, Maicon - so I don't really care.
"I know this is Manchester City and all the big teams need two big players in each position. We always say that big players can win games, but a big squad can win trophies."
City could move to within one point of Premier League leaders Liverpool if they can win at home to Saints on Saturday - and they then face the Reds at Anfield next Sunday afternoon in a game that will surely prove pivotal in the title race.
The challenge for the crown could again come down to the final day, just like two years ago when City claimed a last-gasp 3-2 home win over QPR to pip United to the top prize.
"I don't want the same as QPR, please! That game was incredible," recalls Zabaleta.
"We need to be more focused on Southampton because we can make a big mistake if we're thinking about Liverpool. Everything is in our hands. We need to keep winning - we cannot drop points."
Zabaleta has already won one item of silverware this season but insists: "We know we have a great team to win more than just the Capital One Cup."