What is each club's pedigree? Who are their key players, new faces and ones to watch? UEFA.com has all the answers.
Article top media content
UEFA coefficient ranking (end of 2018/19): 6
How they qualified: English champions
European Cup best: semi-finals (2016)
Last season: quarter-finals (lost on away goals, 4-4 on aggregate, to Tottenham)
Group stage last season: Group F winners – W4 D1 L1 F16 A6 (v Lyon, Shakhtar, Hoffenheim)
In: Angeliño (PSV), Rodri (Atlético), João Cancelo (Juventus)
Out: Vincent Kompany (Anderlecht), Fabian Delph (Everton), Danilo (Juventus), Danilo (Juventus)
Coach: Josep Guardiola
Won six Liga titles and the European Cup as a player with Barcelona between 1990 and 2001, eventually taking charge of the club's senior team in 2008, winning the treble in his first season in charge. Took a sabbatical after a trophy-laden spell with the Blaugrana, resurfacing in 2013 at Bayern – where he won three straight Bundesliga titles. Success his continued since arriving at Manchester City in 2016, with the 2017/18 league title followed by a historic domestic treble last season.
Key player: Raheem Sterling
Outshining the likes of Kevin De Bruyne, Bernardo Silva and Sergio Agüero is no mean feat, but the 24-year-old managed it last season. Scored a career-high 25 goals in all competitions, including five in the UEFA Champions League, and was voted the Football Writers' Association Footballer of the Year and PFA Young Player of the Year.
One to watch: Phil Foden
The 2017 FIFA U-17 World Cup Golden Ball winner has been used sparingly to date but is already the youngest recipient of a Premier League winners' medal and the youngest English player to both start a match and score in the knockout stage of the UEFA Champions League. Still only 19, the creative midfielder will be expected to feature even more prominently this time around.
UEFA coefficient ranking (end of 2018/19): 16
How they qualified: Ukrainian champions
European Cup best: quarter-finals (2011)
Last season: group stage (third place), #UEL round of 32
Group stage last season: third in Group F – W1 D3 L2 F8 A16 (v Manchester City, Lyon, Hoffenheim)
In: Yevhen Konoplyanka (Schalke), Vitão (Palmeiras)
Out: Ivan Ordets (Dinamo Moskva), Wellington Nem (Fluminense, loan), Fernando (Sporting CP, loan)
Coach: Luís Castro
The Portuguese made fewer than 30 top-flight appearance with Vitória SC and Elvas before starting his coaching career at Águeda in 1998. Took his first job in the top division at Penafiel in 2004 and had spells at Rio Ave, Chaves and Vitória SC before replacing compatriot Paulo Fonseca at Shakhtar this summer.
Key player: Júnior Moraes
The striker plundered 26 goals in all competitions last season, including three in their two UEFA Champions League games against Lyon. That level of consistency was no surprise given impressive strike rates at Gloria Bistriţa, CSKA Sofia, Metalurh Donetsk and Dynamo Kyiv before he joined Shakhtar last summer.
One to watch: Tetê
The Brazilian striker made a high-profile move to Shakhtar in February just after his 19th birthday, despite not having made a first-team appearance for Grêmio. The Brazil Under-20 international quickly made a name for himself with two goals in the Ukrainian Cup final against Inhulets and a couple of league efforts.
UEFA coefficient ranking (end of 2018/19): 51
How they qualified: Croatian champions, play-off winners (beat Rosenborg 3-1 on aggregate)
European Cup best: group stage x6 (most recently 2016/17)
Last season: play-offs, #UEL round of 16
In: Luka Ivanušec (Lokomotiva Zagreb), Ivo Pinto (Norwich), François Moubandje (Toulouse)
Out: Ivan Šunjić (Birmingham), Amir Rrahmani (Hellas Verona)
Coach: Nenad Bjelica
Had two spells at hometown club Osijek either side of playing for Spanish outfits Albacete, Real Betis and Las Palmas. Kaiserslautern, Admira Wacker and Kärnten also benefited from the former Croatian international (nine caps), who played for his country at UEFA EURO 2004. Managed four Austrian clubs then had stints at Spezia and Lech Poznań before joining Dinamo Zagreb in May 2018, winning a domestic double within eight days of taking over.
Key player: Bruno Petković
The tall forward had an excellent first season at the club last year, scoring 12 times in all competitions. Received his first Croatia cap in March, grabbing his first international goal three months later.
One to watch: Dani Olmo
A skilful wide man with pace, Olmo left Barcelona at 16 for regular football in Croatia. Reached double figures for goals for the first time last season then scored Spain's U21 EURO final winner this summer to cap a fine tournament.
UEFA coefficient ranking (end of 2018/19): 92
How they qualified: third in Italian Serie A
European Cup best: debut this season
Last season: #UEL play-offs (lost on penalties to København)
In: Luis Muriel (Sevilla), Ruslan Malinovskiy (Genk), Guilherme Arana (Sevilla, loan), Simon Kjær (Sevilla, loan)
Out: Etrit Berisha (SPAL, loan), Federico Mattiello (Cagliari, loan), Gianluca Mancini (Roma)
Coach: Gian Piero Gasperini
After a successful spell as coach in Juventus's youth system, Gasperini took over at Crotone in 2003, leading the southern side into Serie B during his first season before joining Genoa in 2006; again gained promotion in his debut campaign. Had short spells at Inter and Palermo then another three years at Genoa. Appointed Atalanta coach in June 2016, he led his side to the 2017/18 UEFA Europa League round of 32 and finished third in Serie A last season.
Key player: Duván Zapata
The 28-year-old Colombian international had the season of his life last term – the first of his two years on loan from Sampdoria – scoring 28 goals in all competitions. Has the ability to play as a target man due to his physicality and be a goalscoring threat thanks to his power and pace.
One to watch: Musa Barrow
Likely to be behind Duván Zapata and new signing Luis Muriel in the pecking order up front, the 20-year-old Gambian will look to build on a promising campaign last season. Made 30 appearances overall, starting the season with four goals in six UEFA Europa League qualifiers.
Did you know?
- City won 3-0 at Shakhtar and 6-0 at home against the Ukrainian side in last season's group stage. The latter result was then their biggest home European win, later surpassed by the 7-0 defeat of Schalke in the round of 16.
- Shakhtar fared better in their only previous meetings with Dinamo Zagreb, winning home and away to qualify for the 2008/09 UEFA Champions League group stage.
- Dinamo Zagreb qualified from a UEFA group stage for the first time last season (in the UEFA Europa League) after falling at that stage in their previous 13 attempts.
- Atalanta are the only team to be making their group stage debut in 2019/20 – they are the tenth Italian club to feature and the 141st overall.
- While Atalanta have never played Manchester City or Shakhtar, they beat Dinamo Zagreb on away goals in the 1990/91 UEFA Cup first round (0-0 h, 1-1 a).