For the third consecutive match, Roberto Martinez saw his side throw away points thanks to some abject defending; the kind of defending many expected to be on show during the Catalan's first season in charge.
In three games, the Toffees have conceded 10 goals, their joint worst return in any league season.
Such was the promise shown during Martinez's inaugural campaign, this three-game stretch is also the worst of his tenure, and he's already seen his side ship a quarter of their total goals conceded from last season.
So what has gone so horribly wrong at the back?
As dire as both central defenders were on Saturday night, it's too easy to label 32-year-old Phil Jagielka and 36-year-old Sylvain Distin as "past it." Both have produced key performances for the Toffees in very recent times.
Distin partnered John Stones in nine games at the end of last season, of which Everton won eight and kept five clean sheets. Jagielka, meanwhile, was simply immense during games at Old Trafford and the Emirates last term before injury curtailed his season.
That said, both players have been a shadow of themselves thus far, especially Jagielka, and Martinez must seriously consider his options ahead of the trip to West Brom.
Currently, there seems an alarming lack confidence in Everton's back four. The centre-backs are not imposing themselves, and their fragility has spread to those around them—even the ever-reliable Gareth Barry and James McCarthy were poor against Chelsea.
Positionally, as individuals and as a unit, there were basic errors for several goals against Chelsea, and Diego Costa simply tore Jagielka apart. Botched offside traps, a lack of anticipation and communication issues suggest a very basic lack of understanding—not a recipe for lasting success.
Ahead of his side's next game, Martinez has three potential routes: stick with Jagielka and Distin and try to instil as much confidence into their games as possible; drop either for Stones, who must be seriously close to starting; or target another option in the transfer market.
Sticking with them seems likely to remain the initial call. Both players have overcome testing times before and should have the experience and mental toughness to eventually pull through.
Having suffered a 3-0 defeat to Swansea, West Brom are unlikely to provide such a rigorous examination in the next fixture, which could provide a platform to build from.
Stones remains a little too naive and inexperienced to be fully relied on just yet, but his vast potential is obvious and many will champion his selection. He will presumably earn a start at centre-back in the coming weeks, either in the Europa League or Capital One Cup, and any success will make him a hard man to omit.
The final option will be the most attractive one to Evertonians. At this stage, however, it seems the most unlikely avenue with such little time remaining in the transfer market. As time ticks down, prices go up—rapidly.
What's made this even more frustrating for supporters is how such poor defending has come with the Toffees clicking into gear further up the pitch. After decent first halves against Leicester and Arsenal, Everton's attacking play was in full flow against Chelsea.
It's hard to believe, but they actually created more chances than the visitors (15-11) and recorded more shots (17-12), but such was the accommodating defending on show that it all went to waste. Everton have scored the second most goals in the Premier League but have just two points to show for it.
Martinez now has a full international break to plot some kind of recovery. Any continuation of such shambolic defending will quickly derail his season objectives.
Statistics via WhoScored.com.