West Brom head coach Tony Pulis has no doubt Arsenal have a stronger squad than Premier League leaders Chelsea.
A late Olivier Giroud goal saw Arsenal edge past Pulis' side 1-0 at the Emirates Stadium on Monday.
West Brom also suffered a late loss at Stamford Bridge earlier in December, with the result part of Chelsea's 12-match winning run in the league.
While Antonio Conte's side are seven points clear at the top, Pulis believes Arsene Wenger has a better squad at his disposal.
"If you look at the players who were not playing and not in the team today, and then you look at Chelsea's, I think Arsenal have definitely got the stronger squad," he said.
"They have most probably got the staying power to see them through and it will be interesting to see what Chelsea do."
Despite flying high at the top of the table, Chelsea will strengthen in January - according to Pulis.
"I think Chelsea will spend, I don't think [owner Roman] Abramovich will sit back on what he's got.
"It will be an interesting window for the top four or five clubs."
Arsenal sit fourth in the table - nine points adrift of Chelsea and also behind Manchester City and Liverpool.