* Liverpool in tough group with PSG, Napoli
* Holders Real Madrid face tough Roma ties
* Barca in group with Spurs, Inter and PSV
* Bayern drawn alongside Benfica and Ajax (adds details)
By Brian Homewood
MONACO, Aug 30 (Reuters) - Juventus forward Cristiano Ronaldo will face his former club Manchester United after the two European giants were drawn together in the Champions League group stage on Thursday.
Ronaldo, a United player from 2003 to 2009, scored when they beat Chelsea on penalties in the 2008 final after a 1-1 draw and has faced them twice in the competition since with Real Madrid.
The two teams were drawn together in Group H, which also includes Spanish side Valencia and Swiss champions Young Boys Bern, the rank outsiders.
Last season’s Champions League runners-up Liverpool, big-spending French champions Paris St Germain and Carlo Ancelotti’s Napoli were also drawn together in the pick of the groups.
The trio are in Group C with Red Star Belgrade, European Cup winners in 1991 and making their debut in the group stage.
Holders Real Madrid will face last season’s semi-finalists AS Roma plus CSKA Moscow and Viktoria Plzen in Group G.
Inter Milan, back in the competition after a six-season absence, face a tough return in Group B which features Barcelona, Tottenham Hotspur and PSV Eindhoven.
The English Premier League team are the only ones of the four who are not former European champions.
Group E also has three former European champions — Bayern Munich, Benfica and Ajax Amsterdam — alongside AEK Athens.
Pep Guardiola begins his latest bid to win the trophy with Manchester City in Group F where they face Ukrainian champions Shakhtar Donetsk, Olympique Lyonnais and debutants Hoffenheim.
“Manchester City are a massive challenge for us,” said Hoffenheim coach Julien Nagelsmann. “But I was hoping we would draw a big team and we got one.
“Lyon always have good players and Shakhtar have several Brazilians who know how this game is meant to be played.”
Atletico Madrid, AS Monaco and Borussia Dortmund were drawn together in an evenly-balanced Group A completed by Club Bruges.
Roma captain Daniele de Rossi is looking forward to the group stage despite a tough group that includes the champions.
“We picked the best team in the world (Real Madrid) and two others who will create us many problems,” he said.
“Facing Madrid is always great. We’ll go there knowing they are favourites but ready to play our game and give everything.”
Group D features former European champions Porto, Lokomotiv Moscow, Schalke 04 and Galatasaray.
The Champions League has been altered this season, with more places given to teams from the bigger leagues — Spain, England, Germany and Italy now have four guaranteed slots apiece — and fewer from Europe’s less glamorous competitions.
The new system could cut down on the number of one-sided contests which have spoiled the group stage in recent seasons.
But critics say it could increase the competitive imbalance in European football and remove what romance is left.
Writing by Brian Homewood Editing by Toby Davis