Paul McMullan’s first-half own goal was the difference between the two teams, his diving header beating Adam Legzdins after Martin Boyle’s surging run from his own half and subsequent cross.
“I think it was fully deserved which is pleasing,” Gray said afterwards.
"Credit to the players, not just for today, but for the last five or six weeks. Results haven’t been great but performances haven’t always been reflective of results.
“They got their rewards tonight. Martin was electric and we kept asking them questions.”
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Hibs are now preparing for another trip to the national stadium and Gray had a message for the players.
“It is great to get the feel-good factor of winning games and attention now turns towards Sunday. The message is just to look forward to it, because you never know when you might next get the opportunity to play in a cup final – or you might never play in a cup final."
The former Easter Road skipper isn’t yet sure what his role will be come the weekend but he paid tribute to the players for their efforts during his stint in temporary charge.
“A new manager will be quick to find out they are a great bunch of boys. I have worked with them and played alongside the majority of them and the effort and togetherness within the group is there for everyone to see. The new manager will inherit that,” he added.
“I would like to thank the players for their effort and how they have been every single day because it wasn’t an easy situation for anyone. They have been fantastic.”
Gray admitted it was too soon to tell whether the injuries that forced Chris Cadden off in the first half and Kevin Nisbet in the second would affect their involvement in Sunday’s Hampden showdown.
“I am hoping it is more fatigue because they have both played in a lot of games as it has been a congested fixture list,” he explained.
“The good news is that they walked off the pitch, which is always pleasing. We will get them assessed and move on from there.”