Chelsea completed one-half of a possible double last week when they won the Premier League title thanks to a 1-0 victory away at West Brom.

It's the Blues' second title in three years and the first for boss Antonio Conte in his debut season.

The second part of the double awaits them at Wembley on May 27 as they take on Arsenal with the FA Cup on the line.

Although Conte made a few crucial additions last summer like Marcos Alonso and N'Golo Kante, this is largely the same Chelsea side that floundered so badly under Jose Mourinho last season.

To see them dominate like they have this season - largely through Conte's implementation of the 3-4-3 system - is quite the turnaround and the manager must be credited for changing their fortunes.

But, with the Champions League in mind next season, how can Chelsea get any better?

Many believe that Romelu Lukaku is all but set for a mega-money move back to Stamford Bridge and the Premier League top goalscorer has publicly stated his desire to compete for major honours.

However, speaking on Monday Night Football, Gary Neville believes that there is a valid reason why Conte should think twice before adding Lukaku to his ranks.

"Does he buy players to support and get that quality underneath those star players so the gap's shorter?" the Manchester United legend said on Sky Sports.

"Or does he just say 'no, I want to replace like for like'? If Lukaku comes and Costa stays, there's a bit of tension. All of a sudden, how do they handle that tension in the dressing room?

"I think there are some strategic decisions to make over the type of player he buys. Does he buy to improve the XI or does he buy to support?"

All signs suggest that Diego Costa will leave the club at the end of the season with huge offers in China supposedly awaiting him and in that instance, it would make the world of sense to bring Lukaku back to vill that void.

However, if he stays, Neville has a valid point. In such a system as their 3-4-3, there is not room for both men.