The Whites paid tribute to the supporters ahead of kick-off in this weekend's Yorkshire derby win over Sheffield United at Elland Road.
Players and fans laid flowers and messages outside the ground by the remembrance plaque in LS11 while supporters fan-funded a flag in memory of the two - which was on display - and raised money for charity in their names.
Loftus and Speight were both fatally stabbed the night before United's UEFA Cup semi-final first leg against Turkish side Galatasaray in Istanbul in 2000.
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Angus Kinnear led tributes in Saturday's programme while players and supporters took to social media on Monday with gatherings unable to take place.
"While we are custodians of the club, you have our solemn promise that this date will always be appropriately respected," Kinnear wrote.
"Today, we will be wearing black armbands in remembrance of Chris and Kevin, along with Peter [Lorimer].
"The first team will be visiting their plaque at the gates of Elland Road to lay a wreath. It makes me proud that our fans have so much passion to ensure that Chris and Kevin will never be forgotten and while their deaths were both heart-breaking and senseless, I believe that the unity all our supporters show in wanting to remember them would have made them both proud."
Liam Cooper and former captain Lucas Radebe led tributes on social media:
@liam.cooper6 We remember Chris & Kev today. They will never be forgotten. #LUFC #ALAW
@LucasRadebe Horrible scenes in Turkey left a dark hole in my heart never wanted to play that game the boys where brave under the circumstances #RIPKEVANDChris forever #MOT
@ellufc never forgotten. #RIPChrisAndKev
@LPP2014 21 Years. Seems like both a lifetime ago and also like it was yesterday. #RIPChrisAndKev You’ll never be forgotten
@RachaelHTFC No one should go to a football match and never come home 21 years on.... my love thoughts and prayers are with Kevin Speight & Christopher Loftus’ families, friends, loved ones & all at Leeds United today.
@padwar11 Always remembered, never forgotten. Nobody should ever go to football game and not return home. #RIPChrisAndKev #LUFC
@funkyrabbit No one should ever go to a football game and not come home #RIPChrisandKev
@jobleeds28 RIP Chris and Kev. 21 years since that tragic night and Leeds’ darkest hour. Thinking of you, your families, friends and everyone else affected. #RIPChrisAndKev
@NedGonad Rest In Peace, Chris and Kev. Never forgotten. We are Leeds. #RIPChrisAndKev
@aimzk1990 No one should ever go to a football game and not return. Forever with us #RIPChrisAndKev #lufc
@h_arryjones 21 years but never any easier. No one should ever go to a football game and not return home, in loving memory. RIP Chris and Kev #lufc #RIPChrisAndKev
@eltel89 They will never be forgotten. Proud of my club for honouring them every year #RIPChrisAndKev #lufc
@nell_lufc 21 years ago, two of our own went to a football match and never returned. Always remembered and never forgotten. Rest in peace, Chris and Kev #RIPChrisAndKev