NEW YORK — Kayla Thornton has never made a WNBA All-Star team but ask around and you’ll find out that opponents hate to play against her. The ninth-year WNBA vet spent 34 minutes showing exactly why on Friday night in the New York Liberty’s 90-79 win over the Washington Mystics at Barclays Center.

It wasn’t just her career-high 20 points, which came on a season-high four made threes. It was the energy she brought on both ends while filling in for an injured Courtney Vandersloot, as she helped drag New York over the finish line against the winless Mystics.

Liberty coach Sandy Brondello, formerly of the Phoenix Mercury, recalled after the game how she dreaded facing Thornton as an opponent.

“She’s been a thorn in my side for many years,” she said. “Diana [Taurasi] hated playing against her, getting into a few tiffs here and there, a few technicals.”

Breanna Stewart, who turned in an exemplary stat line (18 points, 15 rebounds, five assists) but struggled for long stretches, agreed.

“I was really happy when [Thornton] was coming here because she’s a b**** to play against, excuse my language,” Stewart said. “She’s just really tough and it makes your life difficult.”

Thornton did just that to the Mystics all night, coming up with five steals, the most notable with 8:05 remaining in the game and the Liberty up 70-69. She intercepted an Ariel Atkins pass, taking it the other way for a layup and forcing a Washington timeout.

It was the loudest the nearly 10,000 fans at Barclays Center got all night, and it was for someone who nearly doubled her total season scoring output in one game.

The Liberty called Kayla Thornton's number

 New York Liberty forward Kayla Thornton (5) celebrates after making a three point shot in the third quarter against the Las Vegas Aces at Barclays Center.
Wendell Cruz-USA TODAY Sports

The Liberty don’t give their bench a ton of minutes, and Brondello has faced some criticism for that. However, when you have a starting five loaded with future Hall of Famers and perennial WNBA All-Stars, it can be hard to take them off the court.

Thornton’s minutes had been sporadic, but she knew she’d have to step up on Friday when she learned shortly before the game that she would get the starting nod while Vandersloot rested with a back injury.

“Everything might not go your way and the road might be bumpy, but you gotta stay persistent,” Thornton said. “My teammates just keep me encouraged and stuff like that…It's a long season and it's a lot of games, so you never know what might happen.”

It’s one thing to study tape and scouting reports while going hard in practice. It’s another to translate that into 30 minutes of game action, which can’t truly be simulated. Especially when your minutes fluctuate from 5 minutes one night to 20 the next and 7 after that.

Ivana Dojkic, who played eight minutes on Friday, knows as well as anyone that it’s not easy to suddenly go from the bench to the spotlight.

“Of course we practice every day. We know how to take the shots, how to score,” she said. “But it’s about the mental part of the game.”

Sabrina Ionescu has been a starter her whole career, but she’s seen the work that the Liberty’s second unit — Thornton in particular — has put in.

“It’s really hard to stay ready,” she said. “We all believe in her. We know what she's capable of and she sacrifices a lot to be on this team, and I think we all understand that.”

Thornton made the difference

In many ways, Friday’s game was just as frustrating for the Liberty as the four before it. The Liberty had an excellent first quarter, racing out to a 15-point lead. Again. They had an abysmal second quarter, going cold from the field and letting up defensively. Again.

“We have a good first quarter, then we relax,” Brondello said. “We go away from what, what works the best for us with our being intentional at both ends of the floor…I wasn’t happy at halftime.”

But unlike in their two losses to the Chicago Sky and Minnesota Lynx, the Liberty had someone to make the big plays when they mattered. Ionescu got them going early and finished with 24 points. Jonquel Jones shined in the second half for the second game in a row and finished with 16.

Thornton was strong throughout.

“She never backed down and that was the toughness that we needed,” Brondello added.

Stewart agreed.

“She stepped up big tonight and did what we knew she could,” she said. “She came in off the bench to start and was really confident throughout the entire game and [made] big plays, whether it was threes or steels, she was all over the place and did exactly what we need her to.”

The Liberty will rest on Saturday before facing the Indiana Fever for the third time in nine games on Sunday. It’s part of a marathon stretch where New York plays seven times in 12 days.

With no rest on the horizon, Thornton and the bench are about to become even more important.