Isaias has hailed Adelaide United's maiden A-League grand final triumph as the biggest moment of his football career.
The Spanish midfielder was awarded the Joe Marston Medal as best on ground in Sunday's 3-1 win over Western Sydney, after he lit up Adelaide Oval with a sublime first-half free-kick to put the Reds on course for their maiden title.
Isaias was granted an opportunity to get his name on the scoresheet after Wanderers captain Nikolai Topor-Stanley was shown a yellow card for a foul on Bruce Kamau.
Both the 29-year-old and fellow Spaniard Marcelo Carrusca stood over the subsequent dead ball but it was the former who took it, striking a peach of a shot that lifted over the wall and swerved into the top-left corner.
"It was a little bit lucky, but it was a beautiful goal," Isaias said.
"I want to say thanks to all of my teammates, they help me a lot to play well."
The Reds celebrate Isaias' goal. Image: Getty
The former La Liga player was an integral part of an overall superb Reds performance.
Guillermo Amor's side had the edge over the Wanderers in the first half, and stubbornly resisted them in the second before substitute Pablo Sanchez sealed the result with a 90th-minute strike.
An elated Isaias described it as the biggest moment of his 10-year senior career.
"Yes, 100 per cent," he said.
"This is a special moment in my career ... I'm so proud of my teammates, I'm very happy for all the staff, for all the fans and the city - for everyone."
JOE MARSTON MEDALLISTS:
2016 - Isaias (Adelaide United)
2015 - Mark Milligan (Melbourne Victory)
2014 - Thomas Broich (Brisbane) and Iacopo La Rocca (Western Sydney)
2013 - Daniel McBreen (Central Coast)
2012 - Jacob Burns (Perth Glory)
2011 - Mat Ryan (Central Coast)
2010 - Simon Colosimo (Sydney)
2009 - Ton Pondeljak (Melbourne Victory)
2008 - Andrew Durante (Newcastle Jets)
2007 - Archie Thompson (Melbourne Victory)
2006 - Dwight Yorke (Sydney)