The former Kells amateur has been predominately used in the second-row this season after a switch from centre.
And Holliday received top marks from his coach Carl Forster after Sunday’s 36-4 win over Keighley.
“I think Connor is getting better every game. I thought he was outstanding against Doncaster, and he was one that really stood up last week," Forster said.
“It was the same again in the win against Keighley. He has shown more consistency in his game. He can really play and he is hitting those lines a lot better than he did at the start of the season.”
Holliday is developing into a key player for Haven after nailing down a regular place in the starting line up.
But while Forster was happy to praise the efforts of Holliday for his recent performances, he wasn’t as congratulatory about his team’s discipline.
Discussing the penalty count after the win over Keighley, the coach said: “Some of them were a bit cheap because we gave away a few unnecessary penalties at the end.
“But Keighley are a physical team. You have got to stand up to them and that is what we did.
“As a result, it got a bit scrappy at the end but it is nothing we need to worry about.”
Forster will be looking at discipline ahead of the long trek to Canada next week when Whitehaven cross swords with league leaders Toronto Wolfpack.
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