Barca heavy favorite, even at Emirates
Arsenal vs. Barcelona
This juicy pairing is a rematch from last season's quarterfinals, when Barcelona advanced 6-3 on aggregate. Barcelona briefly trailed 3-2 on aggregate, but four goals from Lionel Messi in the second match assured the Spanish club its place in the semifinals.
This season, Barcelona is the dominant European club with a 21-match unbeaten streak in league play and a plus-59 goal differential. The Blaugrana have also been a dominant club away from Camp Nou, having won 10 straight league matches on the road before Saturday's 1-1 draw with Sporting Gijon. Barcelona's nearly unblemished record and massive goal differential make the three-time European Cup champions the Soccer Power Index's highest-rated team in Europe by far and thus a heavy favorite, even at Emirates Stadium.
Arsenal enters Wednesday's match trailing Manchester United by four points atop the Barclays Premier League table. The Gunners have earned points in their past six home league fixtures and won all three home games during the Champions League group stage, outscoring their opponents 14-2. With nine goals in his past five league appearances, striker Robin van Persie is the man to watch for Arsenal.
Roma vs. Shakhtar Donetsk
According to the SPI, these are the two worst clubs remaining in the Champions League draw. Shakhtar Donetsk is making its first Round of 16 appearance. Roma is back in the Round of 16 after failing to qualify for the Champions League last season. These clubs met in the group stage in 2006-07 season, when each team won at home during the 2006-07 Group Stage.
Roma enters this match in eighth position in the Italian Serie A table, 13 points behind league-leading AC Milan. The Giallorossi have not been in top form lately, winning only two of their past six league matches. They have been a strong side at home this season, however, earning points in eight of their 12 home fixtures with a plus-11 goal difference. That home-field advantage is the primary reason Roma is a significant favorite to win the first leg.
Shakhtar is facing an Italian club for the 11th time in Champions League play and the aforementioned win against Roma marks Shakhtar's only victory. The Ukrainian club's sharpness will be something to watch, as the Premier League has been dormant since Nov. 26, so Shakhtar's last match was a 2-0 victory over Braga in the Champions League group stage.