Portugal international Ronaldo is reportedly seeking a move away from United just under a year after returning to the club from Juventus.
However, a lack of viable options – with Chelsea and Bayern Munich said to have rejected the chance to sign him – has left the 37-year-old superstar in a tricky situation.
Ronaldo's complicated situation has only been exacerbated following United's opening home defeat to Brighton and Hove Albion and a 4-0 drubbing at the hands of Brentford.
With United undergoing another rebuild under new manager Erik ten Hag, ex-United winger Nani can understand why his compatriot is looking to leave.
"Times change and the reactions and attitude can change as well," Nani said.
"But, as we see, he's doing the same things as usual. He doesn't like to lose and he reacts when the team is not doing well. The only difference is that it's different times.
"He's playing again at Man United, but he's been all over the world doing well at different teams with different players.
"He's in a team where the manager is trying to build a strong team, and it's not easy, it takes time. Cristiano doesn't have time to lose on building teams or waiting for next season.
"He wants to continue to be at the top, scoring goals, being the man. That's why the reaction is normal. We all have the wrong reactions sometimes."
Ronaldo was recalled to United's starting line-up for the defeat to Brentford and had six shots, twice as many as any other player on the field, without finding the net.
With its latest dismal defeat, United has started a Premier League campaign with back-to-back losses for the first time since the competition's inaugural campaign in 1992-1993.
Stretching back into last season, the Red Devils have now lost four successive league games for the first time since February 1979.
Nani, who won four Premier League titles and the Champions League during his seven full seasons with United, has hit out at the attitude of the club's current crop of players.
"I don't like to talk too much. I don't talk about players, but you can see there is no hunger, there is no attitude or desire to win in the club," he said.
"You have a lot of talented players, but they don't want to get tired. If I had to get sweaty to win, I would. They prefer to not sweat.
"You have talented players in the team with a lot of skills. They can shoot with their right foot and left, but the last game, no one was shooting at goal, everyone was passing."