Arsenal's Champions League campaign begins tonight with a challenging away fixture against Athletic Bilbao at San Mames. The Gunners are eager to make a strong statement in this season's league phase, especially after last year's painful semi-final defeat to Paris Saint-Germain.

Mikel Arteta's squad is aiming to maintain high spirits after rebounding from a narrow loss against Liverpool with a convincing win over Nottingham Forest over the weekend. However, Arsenal faces significant injury concerns, with captain Martin Odegaard sidelined due to a shoulder issue. He joins Bukayo Saka, Kai Havertz, and Gabriel Jesus on the injury list. There is some positive news as William Saliba is expected to return after recovering from an ankle problem, though Ben White remains unavailable. Cristhian Mosquera, who filled in for Saliba against Forest, could retain his place in the starting lineup.

Athletic Club, managed by Ernesto Valverde, suffered a surprising home defeat to Alaves after winning their first three LaLiga games. They will also be without a key player, Nico Williams, who is out with an injury sustained while on international duty with Spain. Athletic Club reached the semi-finals of the Europa League last season and are returning to this level of competition for the first time since 2014/15.

This marks the first competitive meeting between Athletic Bilbao and Arsenal in Europe. However, the two teams did face each other in a pre-season friendly last month, with Arsenal securing a 3-0 victory to win the Emirates Cup.

The match kicks off at 5.45pm BST at San Mames. In the UK, the game will be broadcast live on TNT Sports and Discovery+.

With several key players missing, Arteta may need to adjust his lineup. Against Forest, Ethan Nwaneri was brought on as a straight replacement in midfield. Declan Rice, who was rested over the weekend, is expected to return to the side. Arsenal's new-look frontline of Noni Madueke, Viktor Gyokeres and Eberechi Eze, who were instrumental in the win against Forest, are likely to get another opportunity to impress. Eze is in line to make his Champions League debut.

Athletic Bilbao's home record is formidable, particularly in European competition, with 14 wins in their last 18 home European ties. Despite Williams' absence, they still possess quality in Oihan Sancet and captain Inaki Williams. Arsenal's strong defense and set-piece prowess helped them reach the semi-finals last season, suggesting that Arteta is unlikely to adopt a more expansive approach despite the new attacking options.