Trinity have lost five of their last six games but they include defeats to promotion-chasing Brackley Town, Stockport County, Harrogate Town and Salford City.
Four of their final five fixtures are against clubs in and around the relegation zone and Sinnott knows the results of those will define their season.
Following Saturday's 1-0 defeat at leaders Salford, Sinnott told Gainsborough Trinity TV: “It was on a knife-edge at times and Salford will know that they’ve been in a game.
“It was reminiscent of a few performances of late. We’ve put a lot in and maybe on another day we’d have got something. I’m really proud of the lads though, to come to a team like Salford and ask them so many questions.
“I told the players that after playing a lot of the top six over the past six weeks, it will help us in the final five games of the season.
“If you can perform against teams right at the top and be unfortunate, it’s important to carry parts of those performances into our final games.”
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