As Phoenix Mercury coach Nate Tibbetts watched the Sparks play the Las Vegas Aces from his home Friday, he was jealous of the electric Crypto.com Arena atmosphere and competitive matchup he saw. It made him excited for Sunday’s game against the Sparks, which exceeded his expectations.

Natasha Cloud scored a career-high 31 points as the Mercury overcame the absence of Diana Taurasi to defeat the Sparks 84-78 after a tense fourth-quarter duel Sunday at Crypto.com Arena.

For Sparks coach Curt Miller, it was not only a disappointing game, but a frustrating one too.

“I’m frustrated that we didn’t play how we were capable of playing,” Miller said. “I don’t think we played with the same spirit, intensity and focus. The No. 1 thing you realize as a coach with a lack of focus is when you struggle coming out of a timeout and look at them in the eye and diagram something and they don’t know where they are supposed to be.

“They don’t execute. That is a frustrating thing for a coach. If we played like we did tonight, Minnesota would beat us by 20 easily. I don’t worry about the wins and losses. I’m worried about playing to our standards, and if we don’t do that Tuesday against Minnesota it will be a long night.”

Despite a career-high 22 points from Sparks rookie Rickea Jackson, Phoenix broke a 78-78 tie when Cloud scored with 35 seconds left in the game. Missed three-point attempts from Aari McDonald and Dearica Hamby in the final 30 seconds helped seal the win for the Mercury (11-10).

Miller said he was proud of the rookie’s performance, which was critical to keeping the Sparks in the game.

“Rickea is a really talented rookie, they guarded her now for the second game in a row in stretches with [Brittney Griner] and we had to find that matchup in a variety of ways to try to isolate [Griner] on the perimeter and also get us moving against [Griner],” Miller said. “For overall growth, I want her to want to take over at times with how they were guarding her. She had a good game. I think it could have been even more of a monster game.”

Hamby led the Sparks (5-16) with 25 points and nine rebounds and Jackson had six rebounds and three assists. Cloud had nine rebounds and five assists, and Mercury teammate Kahleah Copper had 25 points and 10 rebounds while shooting 11 for 13 from the free-throw line.

The Sparks continued to struggle from three-point range, shooting five for 24 while scoring 29 of 75 from the field. Phoenix shot 27 for 59 from the field and 23 for 28 from the free-throw line.

Though the Sparks kept pace early on, they struggled to contain Cloud, who hit a trio of three-pointers and scored 13 points to help Phoenix take a 25-15 lead by the end of the first quarter.

“When you know [Diana Taurasi] is out and you’re a dog like she is, she was going to will that team to the finish line and you need closers,” Miller said. “No one is going to tell [Cloud] she’s not the best player on the floor every time she plays. Attitude is everything, and she was confident in crunch time and we were hesitant.”

Azurá Stevens, making her Sparks season debut after undergoing surgery on her left arm in March, scored her first points on a steal early in the second quarter. She finished with 10 points, six rebounds and four assists. Guard Crystal Dangerfield also made her Sparks debut after signing a seven-day hardship contract Thursday.

For Hamby, Stevens’ return was a positive development for the team.

“Azurá is offensively versatile,” Hamby said. “She’s long, she is active. Defensively it was nice, took a little pressure off for her to guard [Griner] and allow me to roam a bit. We’ve missed her and I know what she’s capable of offensively and defensively. It’s good to have her back.”

After being named to the Australian national team Thursday, Stephanie Talbot, who has been playing significant minutes with an injured right foot, left the game in the first quarter and did not return.

The Sparks clawed back late in the second quarter, going on a 7-0 run to trail 42-39 at halftime. Jackson scored seven points in the second quarter and Hamby had 12 points and seven rebounds at the break.

While Hamby helped make it a one-point game early in the third quarter, foul trouble hampered the Sparks’ efforts. However, the Sparks tied the game 56-56 on a pair of Rae Burrell free throws with 2:13 left in the third. Jackson finished with 10 points in the quarter and made it a two-point game after scoring with 1.1 seconds left.

Midway into the fourth quarter, Hamby scored a three-pointer to give the Sparks a 70-67 lead — their first lead since the first quarter. Both teams traded points down the stretch before the Mercury pulled ahead in the final minute.

Despite losing for the ninth time in 10 games, the Sparks are looking at the positives — they had only nine turnovers and they stayed in the game until the final seconds. They showed that if they can take care of the ball, they can compete. They plan to build on those positives Tuesday against a talented Minnesota team.

“I’m proud of this team,” Jackson said. “We didn’t get the win, but are proud of how we are growing each and every day. I feel like we are trending in the right direction. Wins will come if we just keep coming together and continue to do what we do.”