MADRID, April 29 (Xinhua) -- Atletico Madrid and Arsenal drew 1-1 in the first leg of their UEFA Champions League semifinal at the Metropolitano on Wednesday night, leaving everything to be decided in next week's return leg in London.

Both goals came from the penalty spot, and Arsenal was left aggrieved after a late VAR intervention overturned what had looked a strong claim for a second spot-kick that could have tilted the tie in its favor.

Atletico started with Ademola Lookman on the left and Jan Oblak in goal, with Johnny Cardoso deputizing for the injured Pablo Barrios in midfield. For Arsenal, Eberechi Eze and Bukayo Saka were fit enough only for the bench.

Anyone expecting a repeat of Tuesday's 5-4 thriller between Paris Saint-Germain and Bayern Munich was always likely to be disappointed, as these were two disciplined, tactically astute sides intent on minimizing risk.

Noni Madueke posed the first threat for Arsenal with a powerful run down the right, while Arsenal goalkeeper David Raya saved well from Giuliano Simeone.

Both sides looked intent on staying compact and avoiding defensive errors, with Madueke going close from outside the penalty area while, at the other end, Arsenal was able to close down Atletico's attacks.

Arsenal took the lead from the penalty spot in the final minute of the first half when Viktor Gyokeres was barged over by David Hancko, with the Swede picking himself up and smashing the ball past Oblak.

Julian Alvarez leveled with another penalty 11 minutes after the break after Ben White handled a shot from Marcos Llorente, with the referee confirming the decision following a VAR review.

Antoine Griezmann hit the bar for Atletico in the 62nd minute, and Raya had to be alert to keep out Alvarez's venomous corner as Atletico enjoyed its best spell of the match.

Mikel Arteta made a triple substitution, bringing on Gabriel Jesus, Saka and Leandro Trossard for Gyokeres, Madueke and Martinelli, but Lookman should have put Atletico ahead after a break ended with him shooting tamely at Raya.

Arsenal thought it had another penalty in the 78th minute when Hancko arrived late on Eze after a pass from Saka, but despite clear contact from the defender, VAR overturned the on-field decision.

Arsenal took the initiative after the decision, with Declan shooting just wide and Cristhian Mosquera firing at Oblak, but the score remained unchanged until the final whistle.  ■