Clark hasn't started a Premier League game in more than a month.
Fit-again Florian Lejeune was recalled to Benitez's team at the expense of Clark after last month's home game against Liverpool.
However, Clark, away with the Republic of Ireland for their two-legged World Cup play-off against Denmark, came off the bench against Bournemouth on Saturday after captain Jamaal Lascelles was forced off with an ankle problem.
South Shields man jailed for terrifying physical and sexual assault on woman in her own home
Met Office announces yellow weather warning for thunderstorms across North East following heatwave
Pair set up cannabis farm in town centre flat
Campaigners rally against Local Plan after farmland in Cleadon earmarked for 156 homes
Sea fret - a look at the foggy phenomenon which spoils sunny days in South Shields
Clark, outstanding in Newcastle's Championship-winning campaign, says he accepts the decision of Benitez.
“I felt I was playing well myself, but there was a league game (against Southampton) a couple of days (after Ireland’s win over Wales), and that was the decision the manager made,” Clark told the Irish Examiner.
“Every player wants to play, and I was coming off the back of two good results, but it’s the manager’s decision.
“He’s experienced enough – his CV and his record shows that. If he says that, I’m happy to go with it. Obviously, it’s frustrating sitting on the bench, but I’ll keep working hard.”
Benitez explained his thinking on Clark, signed from Aston Villa last year, late last month.
“We have four defenders," said United's manager. "(Chancel) Mbemba has been playing as a left-back and right full-back, because we didn’t have players for these positions in some games.
“It’s difficult. I was explaining in an interview before – you have to pick 11 players for the game and seven for the bench.
“So that’s simple. It’s mathematics. You have to leave seven, eight or nine players out.
“If you want to play with three centre-backs, fine – they can all play. If you want to play with two centre-backs and a line of midfielders in front, someone has to go to the stands.
“Because Lejeune and Clark were playing well during the pre-season, Lascelles had to improve – and he did that.
“Jamaal’s now doing really well, so Lejeune and Clark are competing. If Mbemba’s right, it’s four.”
Meanwhile, Lascelles' injury is being assessed ahead of Newcastle's game against Manchester United at Old Trafford on November 18.
"Like" our NUFC Facebook page here