Leigh Griffiths has been sensational for the Scottish Premiership side this season but Walker is concerned about the lack of depth.
Newcastle United are set to be relegated if Sunderland beat Everton in midweek.
Tottenham defender Toby Alderweireld capped off a fine season with two awards.
Queens Park Rangers released Alejandro Faurlin and six other players today.
Sheyi Ojo and Jordon Ibe have both been getting first-team opportunities lately.
Gary Rowett's men finished the season 10th in the Championship.
The Baggies manager believes Salomon Rondon will be a different proposition next season after taking time to adjust to life in England.
Mauricio Pochettino's men's three-game winless run has seen them come under pressure for second spot in the Premier League.
The Magpies midfielder admits he "can't really answer" why his side were so lacklustre in their vital clash at Villa Park.
Manchester United are set to take on West Ham United at Upton Park on Tuesday evening.
UBS is introducing a new organizational structure in its flagship wealth management business in a move which aims to cut costs by hundreds of millions of dollars, according to a memo seen by Reuters.
Goldman Sachs’s Dalinc Ariburnu is leaving the firm and being replaced as co-head of sales for fixed-income, currencies and commodities by Jim Esposito.