Laporte, 28, has not featured at all this season after playing through the pain barrier in the final few games of the last campaign and then undergoing knee surgery in May. Pep Guardiola has said previously he does not expect the player to be match-fit until after the international break, but the Spaniard took part in Tuesday's session as he moves closer to a first-team return.
John Stones was also there after missing the Sevilla match with a slight injury, while there appeared to be no issues picked up from the Champions League match last week. The only notable absentee was Kyle Walker, who limped off in the 1-1 draw with Aston Villa and may not be fit again until after the international break.
Also read: Updates from City press conference ahead of Dortmund fixture
The sight of all of his centre-backs in training will have pleased Guardiola, who only had two that weren't injured before a deadline day move was made to bring in Dortmund centre-back Manu Akanji. Akanji started in Seville and is determined to prove that he can play an important role at City.
City are allowed to name 12 substitutes for UEFA games and so could include Laporte if they wanted, but have been known not to fill their bench; Guardiola only picked 10 last week. The manager will give a fitness update on Tuesday afternoon ahead of the game.
Training squad: Ederson, Ortega, Carson, Lewis, Ake, Stones, Laporte, Akanji, Dias, Cancelo, Gomez, Wilson-Esbrand, Rodri, Phillips, Gundogan, Bernardo, De Bruyne, Mahrez, Palmer, Grealish, Foden, Alvarez, Haaland