Orient have already come through one fixture, but a meeting with the Championship outfit will represent a step up in class as they prepare for another League Two campaign.
After failing to challenge for a Championship playoff spot last season, West Brom fans would have been hoping that all energy would be being channeled into righting the wrongs of 2021-22.
However, the revelation that owner Lai Guochuan took almost £5m out of the West Midlands outfit to help his own company is serving as a distraction ahead of the new campaign.
Lai has stated that he will repay the money with small interest by the end of 2022, but fans have understandably been left frustrated that such money cannot be used to sign new players.
Like they did with that acquisition, the Baggies fended off a number of rivals to sign Millwall creator Jed Wallace, while Jayson Molumby has arrived on a permanent deal after his loan spell during the last campaign.
West Brom face having to replace goalkeeper Sam Johnstone, who has signed for Crystal Palace, but as far as his transfer business is concerned, Bruce will have few complaints thus far.
Former Tottenham Hotspur youngster and Cyprus international Anthony Georgiou has also returned to English football, the 25-year-old having the potential to make a difference at Brisbane Road.
On Friday night, Orient got their preparations for the new season underway with a 2-1 win at Haringey Borough with Georgiou and Daniel Nkrumah getting on the scoresheet.
Daryl Dike is expected to be given some game time by Bruce after the United States international missed the majority of the second half of last season with a hamstring injury.
Wellens named two separate lineups for each half against Haringey, and the Orient boss is expected to take a similar approach to this contest.
A further game with Peterborough United is to come later in the week, potentially tempting Wellens out of giving his players any more than 45 minutes each.
We say: Leyton Orient 1-3 West Bromwich Albion
With minutes already in their legs, Orient will be confident of having an edge over their more high-profile opponents during this game. Nevertheless, there may come a time when West Brom's extra quality comes to the fore, which may lead to a relatively comfortable win.
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