Mate in 5 Exercise 81

White plays and wins in 4 moves https://lichess.org/ZdMhvMIu

1. f7+ Kf8 2. Rd8+ Ke7 3. f8=Q+ Ke6 4. Qf6#

The analysis board does checkmate in 5 moves

1. f7+ Ke7 2. Rd7+ Ke6 3. f8=Q Rg5+ 4. Kxg5 Ke5 5.Qf5#

Source:

This publication is in my collection "500 chess puzzles. Mate in 5. Advanced & Expert Level."