Despite having never played a first-team game for Atletico, the 20-year-old found himself at the centre of a transfer saga several weeks ago.
At a time when Conor Gallagher had agreed to sign for Atletico, the Spanish giants wanted to sell Omorodion to Chelsea for a fee in the region of £35m.
Omorodion only scored a modest eight goals from 35 appearances on loan at Alaves last season, yet the finances involved were determined to ensure that both clubs bolstered their positions with financial regulations.
The perception was that Chelsea were also investing in one of European football's top talents, Omorodion having represented Spain at the recent Olympic Games.
However, just weeks after his transfer to Stamford Bridge broke down, the prospect has now moved to Porto for a substantially lower sum.
Porto win race for Omorodion
The Portuguese giants confirmed the transfer on Friday night, Omorodion penning a five-year contract at Estadio do Dragao.
In what is a complex deal, Porto have paid an initial €15m (£12.72m) for 50% of Omorodion's economic rights, with Atletico retaining hold of the other 50%.
Porto have the option of increasing their aforementioned percentage by 15% in each of the following two years for €5m (£4.24m) apiece.
Furthermore, Omorodion possesses a €100m (£84.8m) release clause in his contract, effectively protecting Porto's position.
Why both teams have moved to complete deal
Although Atletico have been able to cash in on Joao Felix and get a high-earner off their wage bill, they have spent in the region of £150m on four new signings.
Money has been generated through other sales, yet selling a player like Omorodion who was signed for a low sum has a notable impact on the books.
From Porto's perspective, they needed to replace Evanilson, their leading marksman who has recently made the switch to Premier League outfit Bournemouth.
Mehdi Taremi had already linked up with Inter Milan on a free transfer, while Toni Martinez is also expected to leave over the coming days.