The Magpies were on course to lose another Premier League contest after Jordan Ayew had put the visitors ahead on the hour mark before Joselu's introduction from the sidelines.
The Spaniard buried his side's equaliser eight minutes after the opener and led the line well during his cameo showing and, in quotes published by the Chronicle, Benitez opted to praise his striker's display.
Indeed, the Magpies boss believes that the ex-Stoke star is proving himself to be a snip at just £5m.
He said: "I think in this new world of football now where everything is so expensive, we knew he could score goals, that he could make a contribution, and he’s doing that.
“Could he score more goals? Yes, but maybe you would have to pay £25million or something like that.
“But he’s doing a great job for the team, he is working really hard and scoring some goals, so I am really happy with him.”
One slightly unsavoury moment for Benitez was Jonjo Shelvey's decision to not shake his hand properly after the midfielder was substituted during proceedings.
It isn't the first time the England international has reacted badly to being hauled off and, in a separate Chronicle article, Benitez reflected on the issue surrounding his and Shelvey's apparent disagreement.
He added: “When you are not winning a game like this one, so important, any player has to be disappointed if they do not continue playing.
“But we have to make the substitutions and that is it. I didn’t have any problems with what he did.
There is a quality player in Jonjo Shelvey. At times, he can be immense. But he is never going to change. His behaviour towards the manager after being taken off was petulant, uncalled for and expected.— NUFC 360 (@NUFC360) January 13, 2018
(You may also be interested in Toon Fans Rip Into Shelvey After Woeful Performance & Benitez Handshake Snub During Swans Draw)
“We were very positive, and had a real intensity and determination to try to score. We were trying to win the game, but I didn’t like the last five minutes when we were making some wrong decisions and giving them the chance to get a counter-attack.
“There were a lot of positives, and some negatives that we have to correct as soon as possible. It would be worse if we were not creating chances. The way that we were working, and the chances we were creating, means that we can do it.
Jonjo Shelvey has now apologised to Rafa Benitez for not shaking hands. #nufc— Lee Ryder (@lee_ryder) January 13, 2018
“We have to carry on doing that, and maybe create more chances if we want to be sure that we go ahead. But we could have scored.”