The Hammers' former assistant manager actually follows in the footsteps of Allardyce by becoming manager of the Tangerines, which was the first club Big Sam managed outright, between 1994 and 1996.
The writing was on the wall for former Everton and Newcastle United player McDonald when Allardyce's contract was not renewed at the end of the season.
At the beginning of last season McDonald was linked with a return to Carlisle United, who he briefly managed in 2006, but decided against going back as the Hammers made their best ever start to a Premier League campaign.
But the East Londoners struggled at the turn of the year, picking up just three wins in 2015 to slide from fourth place down to a disappointing finishing position of 12th.
And now McDonald has told Blackpool's Tangerine TV it is the right time to step out of Allardyce's shadow.
He said: "I'm excited very much to be a number one.
"I've waited my turn to make sure the right place has come up, this is obviously a great opportunity for me and this is a massive football club in my opinion and I'm looking forward to the challenge.
"It feels absolutely brilliant, I've spoken to a lot of people so far and they've wished me all the best. It's going to be hard work but I'm looking forward to it.
"We just have to try and stabilise first of all I think after what happened last year with relegation but then look to push the club on to pastures new.
"I've already spoken to a few players to see if they fancy coming and joining me in this new adventure, and it is an adventure."
Blackpool FC (@BlackpoolFC) June 2, 2015
Whether McDonald returns to Upton Park for some of those players remains to be seen.
But with the club keen to send out a number of exciting young players on loan next season he could well use his relationship with West Ham co-owners David Sullivan and David Gold and the academy staff to his advantage.
It leaves a clear path at the Boleyn Ground for a new management team, which West Ham hope to appoint within the next week.