The Albion defender produced a striker’s finish at the near post after just 12 minutes to assure Blackburn Rovers an essential 1-0 win at home to Sheffield Wednesday.
That was enough to drag them out of the Championship relegation zone, a day after they sacked manager Valerien Ismael.
But the former Derby man has been pitched into testing circumstances after his loan was transferred from Birmingham City.
The relief was obvious as Cashin ran away in celebration after his early strike.
Still up in attack from a set-piece, he got in front of his marker as the ball was driven low across the face of goal.
Eiran Cashin has yet to make an impact with Albion (Image: Simon Dack)
The game was played before a sparse turnout with disillusioned Rovers fans staying away in large numbers.
Damien Johnson is in temporary charge after the departure of Ismael, the boss who had brought in Cashin during the January window.
Johnson gave some idea of the situation in which Cashin has found himself.
The interim boss said: "It didn't matter how, we needed to get over the line. It wasn't brilliant, at times, but I think the players did fantastic.
"We hope this is a turning point for them because it's not been easy. They're an unbelievable group of players so I am very pleased for them.
"They challenged themselves at half-time. We knew they had the long throw, we knew we had to defend our box. First and second balls were always going to be very important. Some, they got first contact but we got most and that was important.
"If you keep a clean sheet, that gives you a good chance to get three points."
Cashin has yet to make an impact with Albion since his arrival from Derby a year ago.
He is under contract with the Seagulls until June, 2030.
As he moved to Blackburn, Albion’s sporting director Jason Ayto said: “Eiran has not had the opportunities we would have liked at Birmingham, and we feel this switch will give him the chance to play more regularly.”