Betfred Super League
Wakefield (6) 16
Tries: Ashurst, Kershaw 2 Goals: Dagger, Lino
St Helens (20) 32
Tries: Lomax, Makinson 2, Roby, Bennison, Dodd Goals: Percival 4
St Helens moved level on points with Super League's top two sides as a clinical display at bottom side Wakefield earned a sixth straight win.
Saints led 20-6 at the break, as Jonny Lomax, Tommy Makinson, James Roby and Jon Bennison all crossed with Matty Ashurst scoring for Trinity.
Lee Kershaw hit back for Wakefield, but Makinson's second try and Lewis Dodd puts the visitors out of sight.
Kershaw scored a late consolation, but Trinity fell to a fourth straight loss.
Third-placed Saints had already clinched their play-off place and will rival Wigan and Catalans for a top-two finish and automatic semi-final spot, while Trinity remain two points adrift of Castleford with three games left to avoid dropping into the Championship.
Saints led early when Konrad Hurrell, returning after a four-match absence with an injured calf, burst through Innes Senior and Romain Franco and fed a pass inside for Lomax to cross within two minutes.
If Trinity were shaken, they quickly regained their composure and were level six minutes later as Franco pounced on Hurrell's slip to race through and pop a scoring pass inside for Ashurst.
Defending champions Saints restored their lead when Jack Welsby's long pass out wide found Makinson who produced an acrobatic diving finish.
The score came against the run of play, and with Hurrell limping off moments later, an undaunted Wakefield went on to boss territory and possession.
Yet they failed to turn their chances into points and were duly punished with a double Saints sucker-punch before the break.
Franco, under pressure from Louis McCarthy-Scarsbrook, dropped a high kick and Roby was there to accept the gift, and moments later Bennison crossed in the corner.
Wakefield badly needed the first score of the second half and soon had it when Jack Croft gave Kershaw a walk-in to cap a slick move.
But another Franco drop gave St Helens more cheap points, spilling the ball to Makinson who ran in from 30 metres for a 174th career score, taking him above Leon Pryce into eighth in the list of Super League's all-time leading try-scorers.
Wakefield kept plugging away, but Bennison's offload gave Dodd a sprint to the line, taking Saints past 30 points and out of sight.
Kershaw added his second try with a late close-range finish and almost broke away for a hat-trick, underlining what might have been for Wakefield who also lost Will Dagger to a suspected broken collarbone.
All four of their Super League wins this season have come in recent months at Belle Vue, and with two of their final three matches on home turf, they will probably need to win both to stand any chance of overhauling Cas.
Wakefield head coach Mark Applegarth told BBC Radio Leeds:
"I thought we left some points out on the field if I'm honest. It's hard to fault anyone for effort, especially some of those defensive efforts.
"We made three or four errors which they scored off the back of, so we need to take a look at that. The key word we keep coming back to all year is composure.
"You play a team like St Helens, that are the benchmark currently in English rugby league, and they feed off your scraps and that's exactly what they did today.
"We've just got to get those smarts about us for the next three games and get that fixed up, keep the effort where it is and we'll get a couple of wins for sure."
St Helens head coach Paul Wellens told BBC Radio Merseyside:
"I'm delighted to get another win and continue the run of form that we're in, but there were some parts of the game where I think, down the track if we are to achieve what we want to achieve, we need to be better.
"There are some lessons to be learned, but this is a difficult place to come, particularly when you come up against a team that are desperate and fighting for their lives. So I'm really pleased that despite not being at our best in certain areas we were still able to get the result.
"There's many teams that if they came here today and coughed up the amount of possession that we did, particularly coming out of our own end, then they would find it very difficult to get a result so there's a lot to like in the way we dug deep for each other."
Wakefield: Dagger, Senior, Franco, Croft, Kershaw, Lino, Gale, Bowden, Hood, Atoni, Ashurst, Griffin, Pitts.
Interchanges: Kay, Battye, Fifita, Eseh.
St Helens: Welsby, Makinson, Hurrell, Percival, Bennison, Lomax, Dodd, Lees, Roby, Delaney, Mata'utia, Batchelor, Bell.
Interchanges: McCarthy-Scarsbrook, Norman, Royle, Mbye.
Referee: Marcus Griffiths.