Confident Trinity were 16-4 up in their Super League opener at Emerald Headingley after Tom Johnstone Innes Senior and Matty Ashurst all scored tries.
Against a depleted Rhinos team, it should have been the bedrock of victory.
However, Wakefield fell apart before the break to go in 22-16 down and eventually lost 28-22.
Chester said: “I am disappointed. For 25, 30 minutes we looked in control; we got it to 16-4, but then I thought we were our own worst enemies.
“We needed to be better at shutting that half down, but fair play to Leeds, they caught us napping a few times, especially on that right-edge.
“There’s plenty to work on defensively, but I thought we threw the ball around okay and scored some good tries.
“We just needed a bit more grit in the tough part of the game.”
That said, there was plenty of encouraging signs for Wakefield, who finished second bottom last year and who face Wigan Warriors on Thursday.
“The guys were really positive in the changing room at half-time and they kind of took over at full-time,” said Chester.
“They knew (compared to) some of the standards we set through pre-season, they weren’t good enough.
“There’s certain standards areas we need to be better at.
“But in terms of togetherness and effort, we are a totally different team to last season.”
Winger Tom Johnstone scored two thrilling long-range tries to underline his credentials to England coach Shaun Wane, who will pick a squad to train in mid-April ahead of the game against Combined Nations All Stars in June.
“We’re fortunate that (assistant) Andy Last works with the England set-up and we’ve seen some things in video that Shaun wants Tom to work on,” said Chester.
“He shouldn’t be far away come the end of year. He’s a special talent and will get better as the weeks go on. He carried the ball really strong and him and Bill (Tupou) were a real handful on that left edge.”