Noah Wyle as Dr. Jeffrey Rosen
It may seem like the perfect crossover of “ER” and “Friends”, but the appearance of Noah Wyle alongside “ER” co-star George Clooney is indeed not a crossover. Yes they both play doctors on Season 1, Episode 17 “The One With Two Parts: Part 2” on “Friends”, however their names are not the same as their “ER” counterparts. On “ER” Wyle plays Dr. John Carter while Clooney plays Dr. Doug Ross; while on “Friends” Wyle is Dr. Jeffrey Rosen and Clooney is Dr. Michael Mitchell.