Alan Pardew brings his rock-bottom Southampton side to south London on Saturday still looking for his first league win some 10 months after his departure as Charlton manager.
"That was a difficult day, but that's football," said Parkinson, who stepped up from Pardew's assistant to take the reins.
"We'd had a difficult time up until then and things have moved on. Now Alan's got a great opportunity at a big club in Southampton and we're looking forward to meeting them on Saturday.
"We've spoken since he left Charlton but it's been difficult since
he got the job at Southampton because we're competing for the same players.
"But I wished him all the best when he got the job and he knows it's a fantastic opportunity for him down there."