Havertz is back after four months out from an opening-day injury, joining Viktor Gyökeres—who cost €63 million from Sporting CP—and Gabriel Jesus in training ahead of Tuesday's Carabao Cup quarter-final against Crystal Palace.
The German led Arsenal's scoring last year with his pressing and link-up play, while Gyökeres brings his 97 goals in 102 games and Jesus excels in set pieces. Top of the Premier League on 39 points, Arteta now has rotation options for a busy festive schedule despite doubts over Ben White and Gabriel Magalhães.