PHOENIX – The 76ers no longer have an unblemished record.

They suffered a 114-109 loss to the Phoenix Suns on Monday night. As a result, the Sixers dropped to 5-1. Meanwhile, the Suns improved to 5-2, their best seven-game start since the 2013-14 season.

Devin Booker, once again, had a huge game against the Sixers.

The Suns guard finished with 40 points, marking the fifth consecutive time that he’s scored 30-plus against the Sixers.

But the Sixers had several opportunities to overcome his scoring production.

They even pulled within 112-109 on a Furkan Korkmaz three-pointer with 3.4 seconds left. But Ricky Rubio responded with a pair of foul shots with 2.5 seconds left to give the Suns their five-point margin of victory.

However, there were a lot of things the Sixers could have done better on this night.

“Defensively just knowing personnel traits in the first half, I think we could have done a better job of that," coach Brett Brown said. “I think that individually in the second half, maybe a more sort of determined effort without fouling. I thought we fouled a lot.”

The Sixers committed 29 fouls with 21 coming after intermission. One foul that nearly hampered them was Tobias Harris’ foul on Kelly Oubre Jr. with the Sixers down 109-106 with 26 seconds remaining.

The swingman converted 1 of 2 foul shots to put Phoenix up four. Harris later fouled out with 6.1 seconds left. Booker, who was fouled on the play, converted both foul shots to give the Suns a 112-106 advantage.

But that wasn’t thing that hindered the Sixers.

“Offensively, I think our backcourt struggled,” Brown said. “I thought Furkan, Tobias and Al [Horford] were really good. The combination of all that [defense, fouls and backcourt struggles] and missing free throws just isn’t going to let you win on the road.”

The Sixers made just 60 percent (12 of 20) of their free throws.

Meanwhile, point guard Ben Simmons and shooting guard Josh Richardson had off shooting nights. Simmons scored six points on 2-for-8 shooting. He had a team-high six assists to go with five rebounds, seven steals and four turnovers.

Richardson had eight points on 3-for-11 shooting. He had five assists, three rebounds and four turnovers. On this night, Simmons, Richardson and reserve point guard Raul Neto combined to have 13 assists and 10 turnovers.

The Suns sagged off of Simmons and him with center Aron Baynes. That tactic enabled Phoenix to cut off his driving lanes.

Horford, however, had his best offensive game as a Sixer.

A free-agent signee this summer, he finished with 32 points on 13 of 20 shooting -- including going 5-for-8 on three-pointers.

He hit buzzer-beating three-pointers at the conclusion of the first quarter and at end of the half. His shot before intermission gave the Sixers a 61-55 advantage.

The Sixers were without Joel Embiid, who served the second game of a two-game suspension for Wednesday’s scuffle with the Minnesota Timberwolves center Karl-Anthony Towns. The Suns were also without their starting center, Deandre Ayton, who is serving a 25-game suspension for violating the league’s anti-drug policy by testing positive for a diuretic.

“For the last couple of games, obviously with Joel being out, I felt like I’ve had to step up a little more, be more aggressive and look to score,” Horford. “Tonight the way they were defending me, it gave me a lot of looks and I took advantage of that.”

In Embiid’s absence, Horford started at center instead of power forward. Harris moved from small forward to power forward. That opened up a spot for Korkmaz at small forward alongside Horford, Harris, Simmons and Richardson in the starting lineup.

Harris added 24 points, a team-high 10 rebounds, two steals and two turnovers. Korkmaz had 20 points while making 4-of-7 three-pointers.

The Suns shot 53.2 percent for the game. But Booker took over the game in the third quarter, scoring the Suns’ first 11 points of the half. He finished with 16 points in the quarter before continuing to do damage in the fourth.

Rubio added 21 points and a game-high 10 assists. Baynes (15) and Oubre Jr. (14) were the Suns other double-digit scorers.

Harris noted the Sixers could have made some adjustments.

“Obviously defensively, I thought they never really felt us in the second half,” Harris said. “They got too many easy look, too many open looks. So I thought that was probably the biggest adjustment.”

Suns coach Monty Williams’ first time facing the Sixers after being the lead assistant to Brown last season. He joined the Sixers’ coaching staff in June 2018 after two years in the San Antonio Spurs’ front office.

The Spurs job came after he spent the 2015-16 season as an assistant coach with the Oklahoma City Thunder. He took a leave of absence after his wife, Ingrid, died in a car accident on Feb. 10, 2016, and after the season, it was announced that Williams would not return.

Before going to Oklahoma City, he had compiled a 173-221 record during five seasons as the New Orleans Pelicans’ head coach. Before that, he spent five seasons as an assistant coach with the Portland Trail Blazers. He also was an assistant coach for the U.S. men’s national team from 2013-16.

Williams said his biggest takeaway from last season was organizing his day again, after having served in the Spurs’ front office.

“Then when I went to Philly, I was like right back into it,” he said. “Brett threw everything at me. He was like, ‘You got the offense.’ I was like, ‘OK.’ It helped me to organize my basketball day again, getting used to sitting up late at night watching film sessions."

Williams said he couldn’t have done what he’s doing as the Suns coach without going through what he did last season with the Sixers.