Oscar's (Matthew Perry) first line to a radio caller in The Odd Couple (2015) is the same first line from the premiere of Go On (2012), in which he also starred.
Besides Felix (Thomas Lennon) and Oscar (Matthew Perry), Roy (David Foley) is the only character that was in all Odd Couple adaptations (play; original film The Odd Couple (1968); The Odd Couple (1970) and The Odd Couple (2015) television programs).
Langford's, the sports bar and grill in the show, is taken from Matthew Perry's middle name: Langford.
A lot of things were taken from the original movie for this episode:
Oscar (Matthew Perry) insisting Felix (Thomas Lennon) move in with him and later sort of regretting it.
Felix doing an about face on the apartment.
Felix chasing Oscar's friends away due to his unusual food and nitpicking.
Teddy (Wendell Pierce) mentioning Felix cleaning the playing cards while playing them.
Felix leaving reminders on Oscar's sports ticker with the initials F.U., which took Oscar two hours to figure out were Felix's initials.
Them going on a date with two sisters who live together in the same building, whom end up bonding over Felix divorce pains and initially see Oscar as the bad guy.
When Felix (Thomas Lennon) and Emily (Lindsay Sloane) realize they share the same Ear; Nose and Throat specialist, Doctor Marshall - this last name is a nod to Garry Marshall, the famous writer/director/producer of both the The Odd Couple (1970) and New Odd Couple television series.