Yeah machine; as he used to run up and down the pitch all game without lapses in concentration.
All sounds pretty bog-standard to me..... "Machine" in football terms usual equates to being a superlative; something way beyond the ordinary.... Kante, Dembele, Lewandowski, Walker for differing reasons have all been described as "machines".
Alonso: Defensively flawed, not particularly quick or athletically gifted WB that is good for the occasional worldie from the edge of the box.