Chelsea have started the season in sensational style, winning their opening eight league games with 26 goals scored and three against.
In the Women's Champions League - the one piece of silverware that eluded Hayes before she left to take charge of the United States women's national team - they sealed their place in the quarter-finals by winning four out of four.
Bompastor led Lyon to glory in the competition in 2021-22, as well as three domestic league titles, and has already set her sights on more success with the Blues.
Manchester City, widely tipped to end Chelsea's stranglehold on the title after missing out last season through goal difference, already trail the leaders by five points after eight games.
So, is the title race already over?
"You don't want to say it, because we're only in November," said former Aston Villa boss Carla Ward on BBC Radio 5 Live. "However, it looks a real tough job for the other teams to catch up.
"It just looks like such a mountain to climb. You're looking at Chelsea dropping points in two or three games and the way they are playing at the minute that doesn't look possible."
Chelsea aren't getting carried away either.
"I think it's still so early and I think so much can change with the amount of competitions we're going to be competing in and the heavy game load," added captain Millie Bright.
"I think anything's possible, anything can change. We saw that last season in how one week we were out of the title race and the next week we were winning it."