Manchester United have drawn Paris Saint-Germain in the last 16 of the Champions League, while Liverpool will face Bayern Munich and Tottenham will take on Borussia Dortmund.
Manchester City were drawn against Bundesliga side Schalke, meaning three of the four English teams will face German opposition.
Cristiano Ronaldo will return to the city of Madrid, with Juventus drawn against Atletico.
Holders Real Madrid must overcome Dutch side Ajax, while Barcelona will take on Lyon and Roma will face FC Porto.
The first legs of the last-16 ties will be split over two midweek dates, on February 12/13 and 19/20, with the second legs played over March 5/6 and 12/13.
It will mark the first time United have faced PSG in a competitive match with Jose Mourinho’s side set to find it difficult to beat the Ligue 1 champions, who were top scorers in the group stages with 17.
Jurgen Klopp goes up against Bayern Munich once again – having lost to them in the 2013 final with Dortmund – and Mills feels his familiarity with the Bavarian giants will help Liverpool.
Dortmund are top of the Bundesliga, nine points ahead of Bayern who have struggled at times under new manager Niko Kovac.
Mills expects Dortmund to provide a stiff test for Spurs, particularly with the second leg at the 81,360-capacity Westfalenstadion.
Schalke are 13th in the Bundesliga and Mills feels Man City boss Pep Guardiola will be pleased with that draw.
The Champions League final will take place on June 1 at Metropolitano Stadium in Madrid.
Full Champions League last-16 draw:
FC Schalke v Manchester City
Atletico Madrid v Juventus
Manchester United v Paris Saint-Germain
Tottenham v Borussia Dortmund
Lyon v Barcelona
AS Roma v FC Porto
Ajax v Real Madrid
Liverpool v Bayern Munich