Shenton had to leave the field round the half-hour mark with a head knock, but confirmed after the game that it was just precautionary that he stayed off.
In his time on the field the Cas skipper had looked strong and showed that he was over the injury that had kept him out of action for so much of 2019.
As for the team, there were some good signs with new signings Danny Richardson and George Griffin showing up well at times, but the players looked a little ring rusty and some of the timing of their attacking plays was a bit off.
They clearly have some work to do ahead of the big kick-off against the same Toronto team, who will likely have the addition of Sonny Bill Williams in their team for the first game of the 2020 Super League campaign.
But the Tigers had enough chances to have won their final warm-up match comfortably and on another day would have come away with a much bigger points haul than the 10 they ended with.
Toronto came up with the first points after four minutes when full-back Gareth O’Brien was sent through a gap near the line by a nicely delayed pass from half-back Josh McCrone. With O’Brien goaling it was 6-0.
Cas forced some pressure of their own with Jake Trueman going on an exciting jinking run, Jesse Sene-Lefao held up just short on the last tackle and Danny Richardson’s grubber kick earning a goal-line drop-out.
The Tigers levelled in the 13th minute as Paul McShane was involved twice in runaround moves with Grant Millington and Sene-Lefao then sent Richardson over.
Richardson added the conversion and that proved the last score of the opening half as there was plenty of endeavour, but a shortage of magic.
Shenton came up with a crunching tackle on O’Brien and made a dangerous burst close to the Wolfpack line. From the latter he appeared to be tackled a little high and soon after was forced off with a head injury.
Cas went close to a further score with McShane losing the ball in trying to reach out over the tryline.
The hosts seemed to take control early in the second half with McShane going close after being unable to take a Millington offload on the line and a second try coming when Tyla Hepi’s superb offload set Richardson free. The half-back then sent winger Sosaia Feki over in the corner for his first try for the Tigers.
But within four minutes Wolfpack replied as Blake Wallace’s break down the middle was backed up by scorer Joe Mellor and Wallace goaled to make it 12-10.
Griffin had a try disallowed for a double movement before the visitors scored again as Wallace this time backed up after an initial break by Thomas Olbison that was carried on by Hakim Miloudi.
Miloudi was sin-binned two minutes from time for a high tackle that took down Lewis Peachey in full flight, but Toronto held on for their win and breathed a sigh of relief when McShane seemed certain to score in the last minute only to drop the ball over the line as he darted through a gap.
Scorers - Castleford: Tries Richardson, Feki; goal Richardson. Toronto: Tries O'Brien, Mellor, Wallace; goals O'Brien, Wallace.
Castleford Tigers: Rankin; Olpherts, Mata'utia, Shenton, Feki; Trueman, Richardson; Griffin, McShane, Millington, Holmes, Sene-Lefao, Milner. Subs: Massey, Clare, Eden, Peachey, O'Neill, Hepi.
Toronto Wolfpack: O'Brien; Kay, Miloudi, Leutele, Russell; Mellor, McCrone; Sidlow, Ackers, Mullally, Dixon, Thompson, Singleton. Subs: Wallace, Springer, Olbison, Wheeler, Cunningham.
Referee: Tom Grant.