The former Watford, Forest, Reading and Sheffield United target man, 34, has been around the block and his arrival could end up proving key over the season.
“We had Hendo get minutes on Saturday and I thought he looked really strong,” said Murray ahead of tonight’s visit of Yeovil Town.
“He gives us another option and he is ready to go.
“He didn’t have a pre-season with us and our boys have worked very, very hard. To just throw him into the League programme would have been very foolish.
“So he has had two and a bit weeks’ personal work now and bits with the lads.
“He trained with the lads on a few occasions last week as well as his personal work and we thought, with the work he had done, he was ready to influence the game.
“After the game he was full of enthusiasm. The character he is, he wants to get going now. He wants to get his teeth into it and start beating people up. We are chuffed to bits with that one.”
When Adi Yussuf went out on loan for six months, Stags might have plugged the gap with an inexperienced player. So to capture a name like Henderson has been a huge bonus.
“That was the idea,” said Murray. “We have Zayn (Hakeem) here who fits the young target man bill.
“We could have gone out and got a young one from non-League who was raw and had this and that potential.
“But it would have been pointless as we would have been blocking the route for one of our kids here.
“What we’ve done with Darius is brought someone in who could affect us now and allow Zayn the time and the environment to grow.
“Zayn is in a great position at the minute. He has a great mentor in Karl (Hawley), who has been there and done it, and he has three senior strikers and can learn from them whatever he wants.
“He has the right ingredients and we are allowing him the time to grow. We will keep giving him his little bit and taking him back out.
“So the signing of Hendo is positive in more ways than one.”
He continued: “We have a lot of influential players in our group at the minute.
“You look at the likes of Pat Hoban, who we’ve not seen yet. For me he is going to be huge for us. So it will be good to get him back in the swing of things.
“Greeeny has come back an animal. I am staying out of his way at the minute as he’s got that look in his eye that he’s ready to eat people.
“I thought Adam Chapman on Tuesday night was outstanding. I think he was back to the Chapman we all know. He was getting around the pitch and his distribution was very good. He made us play.
“So we have got a lot of people I think are going to influence the team and the league this year.
“I have already said I think this is going to be the toughest season I’ve known personally as a player or manager as there are so many good teams.
“You look at the teams and the managers and coaches are more tactically aware. The standard of play has gone up and there is a lot more energy. So consistency is key and it’s those games when you are not at full throttle and understand and recognise that – but you don’t get beat. It’s all about putting points on the board and ticking over.
“Ultimately what will be will be.”