Although they were down to their last 17 available players for the visit of the Challenge Cup finalists, the West Yorkshire delivered a gutsy display in pouring rain at Belle Vue.
Having trailed 14-0, they were just 16-14 behind going into the final quarter and applying plenty of pressure after tries from Innes Senior (2) and Lee Kershaw.
However, Lachlan Coote's try in the 64th minute essentially ended the hosts' hopes of a shock win.
“We've had a good chat about it in there and we feel like we've missed a real good opportunity to beat a good St Helens side," said Chester.
"I thought we showed plenty of character and spirit as well as toughness.
“In the first-half we faced a bit of adversity and came through the other side and we played some really good attacking pieces.
"But in the second-half we had good ball to put a few more scores on.
“We just seemed a little bit disconnected in the second-half with the ball, so there’s a sense of disappointment.
“We don’t get many chances to beat St Helens irrespective of who we’ve got on the field.
"We had to play a winger at nine for longer than anticipated after losing Matty Ashurst to a head knock early on which played a really big part.
“We made too many errors which broke the spirit a little bit, but I’m really proud of their efforts and the guys are doing it tough.
"We’ve genuinely got 17 players fit.”
Hooker Kyle Wood was injured earlier in the week in training and full-back Max Jowitt was pulled out due to track and trace on Thursday.
With fellow hooker Josh Wood also sidelined, winger Liam Kay came off the bench and played nine for most of the game.
Chester said: "I thought Liam did a great job.
"He ran the ball well and his distribution was good and he put his hand up.
"It’s a long time since he’s played half-back - and he keeps telling us he wants to reinvent himself!"