South Africa skipper Graeme Smith was honoured before his 100th Test match - his 99th for South Africa, the other being for a world XI - and Stewart applauded the 32-year-old's achievements.
"It was a tough day at the office for Smith and one he'd have wanted to go better from a performance perspective, but he's a top player and he should thoroughly enjoy what's gone on for him," said Stewart.
"He's had a nice presentation from the South Africa cricket board and the crowd have turned up to support him. Anyone who has captained their country deserves respect, but to do it 100 times is unbelievable."
However, former Kent captain Key, suspects the Proteas leader will be plotting how to oust Pakistan, rather than celebrating, tonight.
"He's got to start working out how to get back in this game," he said.
"He'll think they have a chance and will be telling his bowlers tomorrow morning 'this isn't an easy pitch but we've got to make the most of it. If we get our line and length consistent we should get our rewards'.
"They'll want to put the inexperience of the Pakistan line-up to the test because there won't be too many of them who have played Tests in these conditions.
"There's a really good Test match on offer tomorrow morning."
