The Scottish Premiership season has kicked off today. Celtic will be looking to win the league for the sixth-straight time.

Of course, they came very close to losing their hold over the league title last season, needing a last-day win over Hearts to retain it.

Celtic fans will be hoping for a much more comfortable league triumph this time around. But for that to happen, they will need to strengthen their squad.

Unfortunately, at the moment, some of their best players are busy leaving or trying to leave the club. Kelechi Iheanacho and Daizen Maeda have already bid farewell. And another one could be next, if he gets his wish.

According to a report from Sky Sport reporter Florian Plettenberg, Arne Engels has reached a verbal agreement with West Ham United.

Club-to-club negotiations with Celtic are ongoing. At the same time, the Hoops are working on a deal to sign Mika Baur from SC Paderborn.

In the past, it has been confirmed by reliable sources that Celtic have agreed personal terms with Baur. But so far, an agreement has not been found with SC Paderborn, who seem to be looking for more than what the Hoops have offered to sign the German midfielder.

On the other hand, there have also been suggestions that West Ham United have offered nowhere near what Celtic would want to sanction Engels' exit.

It is worth pointing out that Celtic did turn down an offer in the region of £25 million for Engels in the winter transfer window. So, they would want at least that.

The Baur situation might be becoming a frustrating one for both the club and the fans. It has been quite some time since news broke of the German midfielder agreeing personal terms with Celtic. But since then, there has not been much advancement in the matter.

One has to wonder if it is heading anywhere of note. If not, it might be time for Celtic to look elsewhere. They do not have all the time in the world to find a replacement for Engels.

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Engels' situation is worth talking about as well. This is a player who has been linked with top-level clubs left, right and centre for months.

It is not just teams from the Premier League either. The likes of Napoli and AS Roma are rumoured to be keeping an eye on the Belgian midfielder.

So, one has to question why he is entertaining the idea of going to West Ham United, who will be playing in the Championship next season.

He would be leaving the chance to potentially play in the Champions League for the English Championship. And to be very honest, the Belgian midfielder should be showing a bit more ambition, even if he is intent on sealing a move away from Celtic this summer.