Saturday's game against Derby County is followed by Sunday's trip to Sixfields for Northampton's final pre-season fixture before the big League Two kick-off.
Last season's Premier League surprise package, Birmingham will be looking to build on the three victories they notched up on a recent tour of the far east and boss McLeish will take every opportunity to look at his squad before the top-flight campaign begins on August 14, with two more games next week.
"There will be a strong squad for all four first team friendlies - Derby, Northampton, MK Dons and Mallorca," McLeish told his club's official website.
"I'll mix things up a bit. I have good options for each position and everyone will get a chance to stake their claim."