Arsenal are "absolutely" in a Premier League relegation battle and will be "wondering what has hit them", according to West Brom coach Sam Allardyce.
The Gunners have not played a campaign outside the top flight for more than 100 years but face a fight to steer clear of danger this season.
Having gone seven without a win in the Premier League - one short of their worst ever such run in the competition - Arsenal are just four points clear of the bottom three.
Mikel Arteta's 15th-placed side face Chelsea on Boxing Day, followed by trips to Brighton and Hove Albion and West Brom, two of the teams below them in the table.
And Baggies boss Allardyce, appointed in place of Slaven Bilic earlier this month, expects Arsenal to struggle with their lowly new status.
The Emirates Stadium outfit also exited the EFL Cup with a 4-1 quarter-final defeat to Manchester City on Tuesday, the first time they had conceded four times at home in the competition since a 5-0 reverse to Chelsea in 1998.
Asked on Wednesday if Arsenal were rivals to West Brom at the bottom, Allardyce said: "Absolutely. They haven't won a Premier League game for almost double-figures.
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"Getting beaten last night, even though it was not in the Premier League, drains the confidence of Arsenal's players. They will be wondering what has hit them."
Allardyce and West Brom face champions Liverpool and Leeds United before hosting Arsenal but will be relishing the Gunners' visit.
The former England manager has a reputation for grinding out results with dogged defensive efforts, and it is Arsenal's attack that has badly let them down this season.
They have netted just 12 times in the league - of which two have been penalties - and rank 17th for goals scored.
Arsenal have forged a relatively modest 21 big chances, from which they would be expected to score, which puts the 13-time English champions in a tie for 14th in the top flight.
And the Gunners score with a meagre 8.2 per cent of their total efforts - better only than Sheffield United, Burnley, Wolves, Fulham and the Baggies.
These opportunities are fare rarer than in previous campaigns, too, creating 1.5 chances per game this year, compared to 1.8 in 2019-20 and 2.3 in 2018-19.