The Red Devils signed Uruguayan striker Cavani and Brazilian defender Telles on transfer deadline day.
Cavani, who scored 200 goals in 301 appearances for PSG, has signed a one-year contract at Old Trafford, while Telles put pen to paper on a a four-year deal.
Asked about Manchester United’s new signings, Ighalo said: ‘It’s good for the team, for everybody to be on their toes to work hard.
For a big team, like Manchester United, you have to have competition for players to do well and I welcome the new guys coming in.
They will bring more challenges to everyone in the team, to work hard for their positions to play in the team.’
Ighalo, who joined Manchester United on loan in January, proved a valuable member of Ole Gunnar Solskjaer’s squad last season.
The Nigerian striker has featured in only one of United’s four Premier League matches this term, however.
I’m always ready,’ Ighalo added. ‘Whenever the gaffer calls me, my idea is just to give my best in training, work hard and wait for my opportunity – to take it.
Hopefully, I’ll just keep my head down, keep working hard every day. Come to the training ground every day and give it my best.
Whenever the gaffer needs me, I will come and give my best.‘
Solskjaer’s side face Newcastle United this weekend and will be desperate to bounce back from their 6-1 defeat to Tottenham before the international break.
Ighalo said: ‘We are working hard and looking forward to it.
We’ve been training hard.
Those of us who did not go to the international teams have been working seriously hard.
‘Everyone is in top shape and, when those who have been in the international teams are all back, I think we are in good heart to win the game.
I know we didn’t start the season well so we’ll try to start from this weekend and try to win the game to kick the season off.‘