Sam Allardyce believes Rafael Benitez and Mike Ashley need to move past their personal differences if Newcastle are to avoid relegation.
Saturday's 3-2 defeat at Manchester United, which came after they had taken a two goal lead, has left them joint bottom of the Premier League and still pursuing their first victory after eight games.
Unrest surrounding Ashley's controversial ownership and the perception he has not backed Benitez has led to growing scrutiny of the club, whose unusual regime has also recently been criticised by former manager Kevin Keegan.
Allardyce was sacked by Ashley and replaced by Keegan in January 2008, but while he will have a reasonable understanding of Benitez's frustrations, he believes it remains a manager's job to succeed regardless of the resources he has.
Communication between the Spaniard and Ashley is not good, but the 63-year-old Allardyce told Press Association Sport: "If you're going to be successful, harmony at the top's very important - communication and pulling in the right direction.
"Whether that's happening with Rafa and Mike, I'm not privy to that information, but certainly, from my point of view as a manager, the relationship between the owners and you as a manager is critical.
"(A club) can succeed but you have to put your differences to one side, both the owner and you, as the manager, and work together to get on with the job. Whether you like each other or not doesn't particularly matter; as long as you do the business and the best for the football club.
"I was there for seven months and never really had a relationship with Mike - he wasn't the type. He wanted other people to run the club and he wanted to come along and enjoy the ride. I don't know whether that's changed or not.
"Because (in the transfer market Benitez is) limited, as we all find ourselves with whatever club we're at, we try and use our tactics and the players we've got to the best of our ability.
"The Newcastle fans give (Ashley) a lot of stick, but he is the owner of the football club and he has put his money in. Whether that's enough or not he decides how much money he wants to give the club and it's up to you as the manager to try and spend that as wisely as you can.
"Only time will tell if Rafa has. He certainly did last year; he finished very, very strongly. This year's a difficult start but maybe again they'll come through. New players again - we all have to settle players in very quickly, and that's very demanding as a manager."
Allardyce was asked if he feared his former club were at risk of relegation, and he responded: "Early days yet - we saw West Ham go four defeats on the trot and then they came around against Everton and Manchester United.
"There has to be a bit of light at the end of the tunnel when you score two very good goals in the space of 10 minutes, as we saw at Old Trafford."