Benfica's 2017/18 UEFA Champions League campaign got off to a disappointing start as they were defeated 2-1 by Group A rivals CSKA Moscow at the Estádio da Luz.
Rui Vitória's men took the lead early in the second half through a Haris Seferović strike, before referee Alberto Undiano Mallenco harshly penalised André Almeida for handling in the area, despite his arms being in a natural position. Vitinho dispatched the subsequent spot-kick to level the scores before substitute Timur Zhamaletdinov came off the bench to fire home the winner for the Russians, 19 minutes from time.
It was the Águias that dominated the match, but the visitors started well and went close in the sixth minute when Aleksandr Golovin picked out Alan Dzagoev, who dragged his effort wide from the edge of the area.
Three minutes later, the Encarnados had a good chance to open the scoring when Eduardo Salvio latched onto a fine lofted pass from Pizzi, but the Argentine fluffed his lines on the volley, with the ball rolling harmlessly out of play.
In the 24th minute, the hosts went close when a long-range Andrija Živković strike produced a fine improvised save from Igor Akinfeev, who punched the ball to safety.
Five minutes later, the Russian outfit came within inches of taking the lead when Golovin's strike flew just wide of the far post, with Bruno Varela at full stretch.
In the 36th minute, the hosts very nearly went in front themselves, when Álex Grimaldo struck the outside of the post with a powerful strike from range, with Akinfeev well-beaten.
With half-time fast approaching, Benfica had a decent penalty appeal turned down after Seferović tangled with Viktor Vasin, although it was unclear who had initiated the contact.
Three minutes into the second-half, Benfica went close when Seferović headed an aerial delivery inches wide of the near-post following a corner.
Two minutes later, the Eagles opened the scoring when Živković's left-wing cross found Seferović, who did well to get ahead of his man and divert the ball into the bottom-corner with a delightfully deft touch.
Soon after, Benfica had a great chance to double their lead when Akinfeev spilled a cross into the path of Jonas, but the Brazilian's follow-up shot was smothered by the experienced goalkeeper.
The Russian side had a good opportunity to draw level on the hour-mark, when a corner fell to Swedish midfielder Pontus Wernbloom, but his effort was instinctively turned behind by Varela.
The visitors were awarded a dubious penalty from the resulting corner, after Vasili Berezutski's strike hit the arm of André Almeida, which was planted firmly by his side, and made no movement towards the ball. Vitinho stepped up to fire the spot-kick past Varela and level the scores.
In the 71st minute, CSKA took a surprise lead when Varela parried away a shot from Viktor Vasin, and substitute Zhamaletdinov pounced to turn home the loose ball.
O Glorioso pushed for a leveller by bringing on two strikers; loan signing Gabriel Barbosa came on for his Benfica debut and his first Champions League appearance, while Raúl Jiménez went close in the 89th minute when his volleyed effort drew a smart save from Akinfeev. In the closing stages, Wernbloom was lucky to avoid a second yellow card on two separate occasions, adding to the frustration of the home supporters.
It was simply not meant to be for the Portuguese champions, who fell to their first competitive defeat of the season. The result leaves Benfica third in Group A, without a point but above Basel on goal difference.
Benfica: Bruno Varela, André Almeida, Luisão, Lisandro (Rafa Silva 89'), Grimaldo (Gabriel Barbosa 77'), Salvio, Pizzi, Filipe Augusto, Živković, Jonas (Raúl 69'), Seferović
Goal: Seferović (50')
CSKA Moscow: Akinfeev, Vasin, V. Berezutski, A. Berezutski, Mário Fernandes, Golovin (Kuchaev 87'), Wernbloom, Dzagoev (Natcho 77'), Schennikov, Olanare (Zhamaletdinov 67'), Vitinho
Goals: Vitinho (63'), Zhamaletdinov (71')