Grant brings his Pompey side to the Stadium of Light this afternoon amid intense speculation that the southcoast club are on the brink of adminstration.
Portsmouth officials have denied the claims, but the club's players have received their wages late on two separate occasions and Pompey are currently the subject of a transfer embargo because of unpaid fees they owe their creditors.
Bruce knows all about working in an unstable boardroom environment, having been in charge of Birmingham City while businessman Carson Yeung mounted an unsuccessful takeover bid.
And while players repeatedly insist that they are unconcerned by developments that are out of their control, the Sunderland boss claims the opposite is often true.
The hardest thing for any manager is if there's instability above you, said Bruce.
It's vitally important at any football club that there's stability at boardroom level.
You think it doesn't matter, but eventually it has an impact. It has an impact on the manager, and even though he tries to protect the players, it eventually filters through.I had it at Birmingham, although it was nothing like as bad as it seems to be down there (Portsmouth).
What's happened there is staggering. Two years ago, they were playing against AC Milan in Europe after winning the FA Cup. When you think about the team they had, Jesus, it just shows you what can happen.
Portsmouth and Sunderland both changed hands in the summer, but while the former were taken over by Sulaiman Al-Fahim, only for the club to be sold on to Ali al- Faraj when finances remained tight, the latter have enjoyed a smooth transition into the hands of American businessman Ellis Short.
Having made money available for transfers in the summer, Short has also pledged to support Bruce in the transfer market next month, and the Sunderland boss only has to cast his eyes to Fratton Park to appreciate how fortunate a position he is in.
We're very lucky here because the owner has put his hand in his pockets, he said.
We can't always rely on that, but he's done fantastically well to turn this club around.
You can't keep expecting more and more money, although I hope there is still a bit more to come. But that's what the game has become.
To be in the Premier League now, you have to have a guy above you with deep pockets. If you haven't got that, you'll always be fighting