LONDON, Feb 25: A schoolboy howler by goalkeeper Oliver Kahn cost Bayern Munich an almost certain victory as they drew 1-1 with Real Madrid in the glamour tie of the Champions League's first knockout round on Tuesday.

Holders AC Milan also had to settle for a draw in a goalless first leg at Sparta Prague, but there were wins for Arsenal, who beat Celta Vigo 3-2 in Spain, and Lokomotiv Moscow, who held on for a 2-1 home win over Monaco.

The night will be one to forget for Germany captain Kahn after he allowed a long-range free kick by Real's Brazil wingback Roberto Carlos to slip under his body when he seemed to have the ball well under control.

Voted FIFA's player of the 2002 World Cup, Kahn made his blunder with just seven minutes to go at the Olympic Stadium after Dutch striker Roy Makaay had headed the hosts into a well-deserved lead in the 75th minute.

The away goal means Real, seeking their 10th European Cup, will fancy their chances of making the quarterfinals when they face the Germans at the Bernabeu in a fortnight's time.

Milan will rue a couple of missed chances by Ukrainian striker Andriy Shevchenko in Prague but are confident of improving at the San Siro. The away goals rule will keep Monaco's hopes up after their consolation strike by Fernando Morientes in a snow-swept game in Moscow.

Goals from Marat Izmailov and Vladimir Maminov looked to have secured a convincing win for the Russians, but the Spaniard's header and a bad miss by Lokomotiv's Nigerian substitute James Obiorah kept the French Ligue 1 leaders well alive.

The away goals rule will give little encouragement, though, to Celta Vigo who were outgunned by in-form Arsenal. Twice behind to goals from Brazilian midfielder Edu before losing to a late winner by France winger Robert Pires, the Spaniards know Arsenal can afford to lose 1-0 or 2-1 at Highbury and still reach the last eight. -Reuters