Koeman has secured the big-money Everton signings of Jordan Pickford, Michael Keane and Davy Klaassen while Sandro Ramirez and Wayne Rooney have also been brought in - but a natural replacement for Romelu Lukaku is yet to be found. "Clearly, Wayne Rooney has the ability to fill that space", said Hughes, who had a brief spell at Goodison Park towards the end of his playing career.
With only one defeat to Stoke in the last five meetings and an unbeaten pre-season schedule that included a 2-0 aggregate Europa League victory over MFK Ruzomberok, Everton will be likely favourites for Saturday's match.
But the manager concedes that, for all Everton's shrewd business, it may only allow them to stand still, at least in terms of league position.
"I know the expectations are higher than last season, but I always look to be realistic", said Koeman.
The striker looks to have the physicality and keen eye for goal to thrive in the Premier League, but does he have the right mentality?
"Okay, I believe if we get the picture of the last players we are stronger than last season but being stronger than last season does not mean you will win against the big six because they also will be more strong than last season".
Morata contributed 15 LaLiga goals despite starting only 14 league games for Madrid last season and Chelsea need him to make an immediate impact, with star man Eden Hazard out for the opening weeks as he recovers from an ankle injury. "We are looking forward to getting started".
Stoke, who won their last away Premier League game on the final day of last season at Southampton, haven't recorded back to back away league wins since October 2015.
Everton have had deals worth up to £40 million and £45 million rejected for the Iceland midfielder this summer but Koeman said: "We are close". They've bought in players, spent money and they are having a go though, so fair play to them. "I heard some rumours that the talks broke down but we are still in negotiations with Swansea".
"They've brought good players in but lost key players too, like Lukaku".