Mikel Arteta admitted Arsenal looked tired in their slender 1-0 Champions League win over Shakhtar Donetsk at the Emirates. The Gunners bounced back from their surprise defeat against Bournemouth after Gabriel Martinelli’s first-half strike rebounded in off goalkeeper Dmytro Riznyk to maintain their unbeaten record in Europe. But Leandro Trossard missed a second-half penalty and David Raya had to produce a fine stoppage-time save to be sure of the three points. Arsenal’s evening was also soured when Riccardo Calafiori limped off with a knee injury in the second half.