The Champions League knockout phase play-offs begin this week, with 16 clubs competing to join the eight that have already advanced to the final 16.

Manchester City and Celtic are among those looking to advance from their two-legged matches against European champions Real Madrid and Bayern Munich, respectively.

But which clubs made it to the playoffs? And who is already done?

Who has advanced, and who is in the playoffs?

Manchester City came from behind to defeat Club Brugge and earn a spot in the play-offs, while Aston Villa and Arsenal joined Liverpool, who had already secured their spot, with automatic advancement to the final 16.

Celtic, who lost 4-2 to Aston Villa in their last league game, joins City in the play-offs, as all five British clubs advanced from the regular phase.

These are the teams who progressed to each stage:

Last 16 teams: Liverpool, Barcelona, Arsenal, Inter Milan, Atletico Madrid, Bayer Leverkusen, Lille, and Aston Villa.

Knockout phase play-offs: Atalanta, Borussia Dortmund, Real Madrid, Bayern Munich, AC Milan, PSV, Paris St. Germain, Benfica, Monaco, Brest, Feyenoord, Juventus, Celtic, Manchester City, Sporting, and Club Brugge.

And we already have an idea of who could play who in the next rounds – with City and Celtic in particular about to face huge tests.

Which clubs have advanced to the playoff round?
The complete draw for the playoff round is as follows:

Brest vs. Paris St-Germain (first leg, 11 February; second leg, 19 February)

Juventus against PSV Eindhoven (First leg, 11 February; second leg, 19 February)

Manchester City vs. Real Madrid (first leg, February 11; second leg, February 19).

Sporting vs. Borussia Dortmund (first leg, 11 February; second leg, 19 February)

Club Brugge against. Atalanta (first leg, February 12; second leg, February 18).

Celtic vs. Bayern Munich (first leg, February 12; second leg, February 18).

Feyenoord vs. AC Milan (first leg, February 12; second leg, February 18).

Monaco vs. Benfica (first leg, February 12; second leg, February 18).

Who may meet in the last sixteen?
After finishing in the top two in the league phase, Liverpool and Barcelona will be unable to meet until the final.

In the final 16, the Reds will face either Monaco, Brest, PSG, or Benfica, while Barcelona will face another of those clubs.

Arsenal, who finished third, will face Feyenoord, Juventus, AC Milan, or PSV.

Aston Villa, who just finished in the top eight by defeating Celtic, will face Sporting, Club Brugge, Atalanta, or Borussia Dortmund.

The ties will be held on March 4-5 and 11-12.

However, they won’t know which team until the last-16 draw on February 21.

Clubs will know their likely path to the final before then, since the quarterfinal and semifinal drawings will also take place on that day.

Which British clubs might potentially meet in the future?
If both Liverpool and Aston Villa win their last-16 matches, they might meet in the quarterfinals.

Arsenal might face Celtic or Manchester City in that round.

However, all of those prospective matches are determined by the outcome of the last-16 draw. It is also feasible that British teams will meet in the semifinals or final.

All should become obvious following the draw for the final 16 on February 21.

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