Arsenal manager Mikel Arteta has jumped to the defence of Bukayo Saka following a string of underwhelming performances from the England international. The academy graduate was substituted after a disappointing hour-long cameo against Bayer Leverkusen in the Champions League on Wednesday night, sparking concerns about his current physical and mental state.The Arsenal forward was hooked during the midweek Champions League trip to Bayer Leverkusen, having struggled to exert his usual influence on proceedings. Meanwhile, his replacement, Noni Madueke, made an immediate impact by winning a late penalty for the Gunners. In previous seasons, the telepathic understanding between Saka, Martin Odegaard and either Jurrien Timber or Ben White on the right flank served as the team's primary source of goals, but injuries and personnel rotations have disrupted that chemistry.Despite the scrutiny, Arteta insists that his faith in the England international remains unshaken. "We fully trust him and love him," the Spaniard insisted. "What he's doing for us, for this club, is just incredible at his age and he's continued to have that massive impact for us. He can have an individual performance that is not probably a reflection of his level, like every human, every player in the world. But overall when you look at his strength and the impulse he has in the team, it's just incredible."Beyond any tactical tweaks, the sheer volume of football Saka has played is beginning to catch up with him. Arteta admitted that the winger’s workload has already surpassed the levels seen in previous campaigns, suggesting that fatigue is a major factor in his recent inability to influence games. Having played virtually every minute for both club and country over the last two years, the relentless schedule is perhaps finally starting to show in the youngster's tired legs and diminished spark."The amount of games and minutes he's played now, it's a bit more already than the whole of last season," Arteta noted. "We also just have to understand the demands we're putting on players. That's another thing that obviously when we talk about the beauty of the game, all these things affect certain things for sure."Add GOAL.com as a preferred source on Google to see more of our reportingWith the Champions League knockout stages and the Premier League title race both intensifying, Arsenal need their leaders to step up. For Arteta, Saka remains exactly that, regardless of the noise from outside the Emirates. The focus now turns to reintegrating injured stars to provide Saka with the familiar support system he needs to return to the world-class form football fans have come to expect. Indeed, Saka is likely to be involved and will hope to play a pivotal role when the Gunners host Everton this weekend.