The Spaniard was drafted in last month to replace caretaker duo Keith Downing and Dean Kiely following Steve Clarke’s dismissal before Christmas.
Mel earned a reputation for his managerial heroics in his homeland with Real Betis, but has been unable to guide the Baggies to a single victory during his six Premier League games – although he did secure a good point against high-flying Liverpool.
It is understood that a heavy loss in their next fixture against Manchester United at The Hawthorns could secure the 50-year-old’s fate with patience in the boardroom dwindling.
Some senior players are also thought to be concerned by Mel’s tactical approach and team selection, which has led to murmurings of discontent among the squad.
West Brom are currently hovering just above the relegation zone, and know that a strand of poor results could be enough to see them lose their top flight status.
Downing and Kiely could take charge if Mel is sacked, with the duo having guided the Midlanders in their absence of a true manager.