- Lionel Messi scores twice to help Barcelona thump BATE Borisov 5-0 in Belarus
- The double strike means Messi is now joint second in Barca's all-time scoring list
- Alex Oxlade-Chamberlain becomes the youngest Englishman to score in Champions League
- The 18-year-old helps Arsenal to beat Olympiakos of Greece 2-1 at the Emirates Stadium
Lionel Messi scored twice for Barcelona as the European champions crushed BATE Borisov 5-0 to claim their first Group H win in this season's Champions League.
Barca opened the scoring in the 19th minute of a wet evening in Belarus, when Alyaksandr Volodko turned a Dani Alves cross from the right into his own net and they doubled their lead three minutes later when Pedro headed home David Villa's left-wing center.
Goalkeeper Alyaksandr Gutor gifted Barca their third, dropping Pedro's cross onto Messi's head for the Argentine's first goal of the night, while Messi added his second soon after the interval -- firing home after exchanging passes with Alves.
Messi has now scored 14 goals already this season and takes his total number of Barcelona goals to 193, joint second with Hungarian Ladislao Kubala in Barca's all-time list of leading scorers.
Villa added a last-gasp fifth goal for Barca, after BATE had made a mess of a free-kick, as the Catalan giants equalled their biggest-ever Champions League win.
Barcelona are level on four points with Milan at the top of the group, after the Italian champions saw off Czech side Viktoria Plzen 2-0 at the San Siro.
Milan opened the scoring in the 53rd minute when Zlatan Ibrahimovic marked his return from injury by netting from the penalty spot after Marian Cisovsky handled in the area.
And Ibrahimovic set up Milan's second 13 minutes later, holding off his marker before slipping the ball through for Antonio Cassano to deftly find the net.
BATE Borisov and Viktoria Plzen are joint third on one point apiece and already look to have a mountain to climb against the two giants of the group.
Chelsea are top of Group E with four points from their first two matches, despite conceding a late penalty in a 1-1 draw at Spanish side Valencia.
England midfielder Frank Lampard, who was restored to the side by manager Andre Villas-Boas after being left out of their weekend win over Swansea, opened the scoring in the 56th minute when converting Florent Malouda's pull-back.
But, just three minutes from time, Roberto Soldado levelled from the spot after substitute Salomon Kalou handled a cross in the area.
Bayer Leverkusen are second in the table with three points after a 2-0 home victory over Belgian champions Genk.
Lars Bender opened the scoring on the half hour mark, slamming home a shot from a tight angle, and veteran midfielder Michael Ballack sealed the win in injury time with a superb volley -- his first goal in more than 18 months.
Valencia are third in the table on two points, after drawing their opening two games, with Genk propping up the others with just a single point from their two matches.
In Group F, Arsenal winger Alex Oxlade-Chamberlain entered the record books as the London side beat Olympiakos 2-1 at the Emirates Stadium.
Chamberlain, 18, opened the scoring with a composed eighth minute finish to become the youngest-ever Englishman to score in the competition.
Brazilian left-back Andre Santos scored his first Arsenal goal from a tight angle to double their lead before David Fuster pulled a goal back with an unmarked header from inside the area.
Arsenal are second in the table with four points, two behind French champions Marseille, who lead the way with a maximum six points after cruising to a 3-0 home win over Borussia Dortmund.
Andre Ayew gave the hosts a 1-0 half-time lead when he fired home a low shot from outside the area and they doubled their lead in the 62nd minute when Loic Remy blasted home after superbly chesting the ball down.
Ayew added his second, and Marseille's third, seven minutes later, converting from the penalty spot after Remy had been bundled to the ground by Dortmund captain Sebastian Kehl.
The only down side for Marseille was the late dismissal of Jordan Ayew, who was shown a second yellow card for diving.
Meanwhile, Russian champions Zenit St Petersburg battled back from going behind to claim a 3-1 Group G win over 10-man Porto.
Europa League winners Porto went ahead in the 10th minute when Colombian James Rodriguez netted from Hulk's right-wing cross, but the home side drew level 10 minutes later when Roman Shirokov scored from the edge of the area after goalkeeper Helton had deflected a Viktor Faizulin cross into his path.
Porto had defender Jorge Fucile sent off for two yellow cards just before the break -- and Zenit took control in the second half.
Shirokov scored his and Zenit's second when converting from close range and Danny added a third 18 minutes from time when turning home Alexander Kerzhakov's cross.
However, surprise leaders of the group after two matches are Cypriot side APOEL Nicosia, who drew 1-1 at last season's quarterfinalists Shakhtar Donetsk.
That result leaves APOEL on four points, with Zenit and Porto on three apiece and Shakhtar trailing on a single point.