A European manager would face certain challenges in taking over at the Phoenix given the club plays in a league with a salary cap and tight restrictions around foreign players.
Some have suggested someone with experience in the A-League would be a better option given local knowledge could prove advantageous.
Merrick had a successful spell managing Melbourne Victory from 2005-2011 and last coached the Hong Kong national side but finished his role with them late last year.
Chris Greenacre served as the Phoenix's interim head coach for the back end of the A-League season after Ricki Herbert resigned in February but Greenacre said he didn't want the top job in a full-time capacity and didn't apply.
Meanwhile, midfielder Alex Smith said his goodbyes to the club and their fanbase on Twitter this afternoon.
The 27-year-old arrived at the Phoenix in late 2011 and signed a string of short-term deals before eventually finishing the season with the club.
He penned a one-year deal for the season gone and it's understood the club didn't make much of an effort to keep the versatile player who dropped in and out of the squad all summer.
Smith, who has played in various lower-level sides in Australia and was on the books of MLS club FC Dallas from 2005-2006, tweeted: ``I'd just like to thank the knowledgable (sic) @WgtnPhoenixFC supporters during my time there...''
And the new father also offered: ``Not sure where I'm headed yet...enjoying my baby boy at the moment....thanks for all the love and appreciation.''
