With Chico Flores ruled out with ruptured ankle ligaments, it is between Bartley and club captain Garry Monk for the central-defensive slot alongside Ashley Williams.
Bartley had a frustrating start to life in south Wales after a thigh injury kept him out for three months, but he has made an impression with his strength and reading of the game since returning to full fitness.
Last summer's decision to leave Arsenal after three years in north London, was a difficult one to make, but the impact of facing Swansea during his time on loan at Sheffield United helped sway him.
"I remember I played against Swansea when they were in the Championship, we played them at Bramall Lane and we won 1-0," he said.
"I spoke to my Dad after the game and I said to him 'I love the way they play the game'.
"I kept a close eye on them last year in the Premier League and as a team they really interested me and when the offer came in it was very exciting.
"Because of that I never saw this move as a backward step, I saw it as a chance to play at a Premier League club who played a brand of football I enjoy. It has been a fantastic season and hopefully we can top that off by winning on Sunday."
Bartley is understandably desperate to be involved when the Swans go in search of the club's first major honour, but the former England age-grade international has vowed to put any personal disappointment to one side should he not make the starting XI.
He said: "Personally it will be very exciting to be involved in a final but as far as the team goes I need to prepare as if it is a normal game and be ready to play.
"I cannot afford to get too down if I am not picked, whoever is selected the other guys will need to congratulate them and get right in behind them because we are a team."
If selected to partner Williams, Bartley will relish the chance to play alongside a centre-half he rates as one of the best around.
"I think he is right up there," said Bartley.
"I agreed with (Wales manager) Chris Coleman when he said Ash was one of the form centre-halves in the Premier League.
"He has been fantastic, he has been a real leader and taken games by the scruff of the neck.
"He is so strong and everyone in the club respects him as a player and a person, he is a great guy to be around."
Sunday will not be Bartley's first experience of Wembley, while at Bolton in 2007 he played in the England Under-16s team which defeated Spain 1-0, thanks to a Jack Rodwell goal.
He said: "I have some special memories of playing at Wembley for England at age group level at Wembley, and hopefully there will be another positive result to add to those memories this weekend."