The meaning of the word lagging behind above is that Al Ahli is currently experiencing a decline and their position in the standings is in the middle of the table, unlike last season where Al Ahli was involved in the competition with Al Nassr and Al Hilal, and yes, now we can forget about Al Ahli, they might have difficulty catching up because the distance between their points and the top three is currently quite far.
While we've seen the competitiveness in the performance of Al Hilal, Al Ittihad and Al Nassr, which are currently occupying the first, second and third positions of the table standing, respectively, Al Ahli have continued to fall lower the league's table standing due to their consistent underperformance this season. What I think have caused this in my humble opinion is the coming of the new coach who came in from Red Bull Salzburg. Mattias Jaissle since his arrival haven't been able to handle the pressure emanating the team as he continues to lag in his formation adjustment and uncertainty in his tactics or squad management. Since the Brentford player Ivan Toney came in as a result of his transfer to Al Ahli, it has made the club's performance more weakened instead of the opposite.
I wonder why the coach is also finding it difficult to position Mahrez and Firmino in the proper positions and I feel that has really affected the attacking of the club. I also think this new 4-2-3-1 formation which has taken Toney to the forefront of the attack hasn't really given great results. Even when they got opportunities in their previous match against Al Ittihad, they couldn't deliver goals as the finishing point was kinda weak to my reasoning. The Al Ahli team's got pretty talented players and could perform well this season but the coach really needs to put in a lot of efforts towards understanding and improving on the tactics of the team and by undergoing more rigorous training of the players to understand better.