The legendary Welshman has been in temporary charge of the club since former boss David Moyes was relieved of his duties last month and has so far led his side to a 4-0 win over Norwich City and 1-0 defeat to Sunderland - both on home soil.
Tuesday's visit of FA Cup finalists Hull represents United's final home match of a disappointing 2013-14 season, which has seen them lose seven Premier League fixtures in their own back yard.
But while the match offers United the chance to bring the curtain down on a sorry home campaign, it could well be the end of the line for the club's longest servant on the pitch.
"It might dawn on me on Monday or Tuesday," he is quoted as saying by BBC Sport. "Then I might have to put myself on the bench."
Last season's final match at Old Trafford saw Sir Alex Ferguson depart having lifted the Premier League trophy, and Giggs - a man of similar standing with United fans having made 962 appearances for the club - is hoping for his own fairytale ending.
"The perfect scenario would be me coming on and scoring but football doesn't work like that," he added.
Giggs admits his playing future will be decided when the new manager - Louis van Gaal reported to be in pole position - arrives, but one man who is definitely making his final Old Trafford appearance is Inter-bound defender Nemanja Vidic.
"Vidic has been a brilliant player over the years, probably the greatest defender I've played with and I've played with some good ones," said Giggs.
"But he's right up there. He's a brilliant player and he'll be sorely missed."
Vidic's long-time colleagues at the back Rio Ferdinand and Patrice Evra could also be bidding an emotional farewell, with their contracts set to expire at the end of the season.
Opponents Hull are already assured of safety and a place in next season's UEFA Europa League, so are likely have more than one eye on their Wembley date with Arsenal on May 17.
However, the KC Stadium outfit made United work for their win in the reverse fixture, squandering a 2-0 lead in a 3-2 defeat.
Wayne Rooney remains a doubt for Tuesday after missing United's defeat to Sunderland with a bug and a minor groin complaint.
For the visitors, James Chester will miss out after injuring his hamstring in Saturday's 3-1 defeat at Aston Villa, the issue is expected to also keep him out of the Cup final, while Sone Aluko, Paul McShane (both ankle) and Allan McGregor join the defender on the sidelines.
