The 18-year-old defender arrived at Elland Road in the summer from Celtic, penning a four-year deal to end a lengthy pursuit of his services by sporting director Victor Orta.
A Norwegian international at youth level, Hjelde boasts a wealth of experience in the academy ranks and in the Scottish Premiership having spent time on loan at Ross County.
He has made nine appearances in the Premier League 2 this season for Leeds - mainly at left-back - but made a good impression during Sunday's FA Cup clash with a battling performance in the capital.
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His first start came alongside fellow academy prospects Sam Greenwood and Lewis Bate amid mounting injuries at Elland Road, though while the other two were half-time substitutes Hjelde remained on pitch until the latter stages.
He was forced to take on seasoned professional and Hammers dangerman Michail Antonio as the hosts named a strong line-up for the clash - including the likes of Jarrod Bowen, Manuel Lanzini and others.
“We had some young lads playing who did really well and we got stuck in, especially in the first half," Ayling reflected on United's third round exit to the Hammers.
“Sam Greenwood and Lewis Bate came off at half-time but I thought they played really well.
“Then there is Leo Hjelde at the back. You don’t get many bigger tests than facing the big man up top, Michail Antonio, but I felt he handled himself really well.
“We had Cody [Drameh] coming on from the bench as well, so we’ve got a good bunch of young lads coming through."
Drameh - who was a second half substitute for full-back Junior Firpo - is set to head out on loan to Championship outfit Cardiff City, despite the growing injury list at Thorp Arch.
Bielsa is currently faced with mounting treatment room problems ahead of this weekend's trip back to face the Hammers in Premier League action on Sunday.
Leeds have been left severely short across the board and, particularly, up front due to problems for Patrick Bamford, Tyler Roberts, Joe Gelhardt, Rodrigo and now Greenwood, who revealed he had picked up a knock himself on social media.
Kalvin Phillips and Liam Cooper are also longer absentees while Jamie Shackleton and Charlie Cresswell are battling for fitness alongside Pascal Struijk.
To add to the Whites woes, Firpo left the field of play due to an apparent head knock though no update over his condition has been made as yet.
Diego Llorente is also suspended this weekend to deepen the crisis facing the Whites.
Asked about the defeat in the capital to David Moyes' men which came in controversial circumstances, Ayling added: "For the first goal I am not quite sure what happened, I think everyone thought it was offside. I’m not sure what was checked on it.
“Goals change games and they are so strong, so well coached, so that first goal was always going to be vital.
“In the second half we stayed in the game but they probably made enough chances to win the game and like I said, it’s a tough place to come.”