The three-time All-Star guard could miss his second straight game due to left foot soreness when the Suns host the Utah Jazz on Saturday night. He is listed as doubtful.
Booker sat out Thursday against the Los Angeles Lakers, and Phoenix faded late in a 100-95 loss.
That continued a trend from last season when the Suns were 34-19 in the regular season with Booker and a measly 11-18 without him.
After Booker sustained a groin injury against the Denver Nuggets on Christmas night, an ailment that kept him out for six weeks, the Suns won their following game before losing nine of their next 10.
Booker was in the lineup for the season opener on Tuesday and had 32 points, eight assists and six rebounds in a 108-104 victory over the Golden State Warriors in San Francisco. Booker injured his foot during the contest.
Phoenix shooting guard Bradley Beal (back) will miss his third straight game. The three-time All-Star was acquired from the Washington Wizards in the offseason.
The absences of Booker and Beal were certainly felt in the road loss to the Lakers as the Suns were outscored 28-11 in the fourth quarter.
Phoenix’s Kevin Durant was a virtual one-man band, hoisting 28 shots — making half of them — while scoring 39 points. The team’s second-highest scorer was Eric Gordon with 15.
Durant, 35, completed the night as the 12th-leading scorer in NBA history with 26,949 career points. He surpassed Houston Rockets legend Hakeem Olajuwon (26,946).
New Phoenix coach Frank Vogel enjoyed the competition between Durant and LeBron James (21 points), the latter of whom Vogel coach for three seasons with the Lakers.
Now the Suns will look to defeat Utah for the 10th time in 12 meetings.
The Jazz also split their first two games, but they will bring momentum into the outing against the Suns after recording a 120-118 win over the Los Angeles Clippers on Friday in Salt Lake City.
Jordan Clarkson buried the go-ahead 3-pointer with 28.9 seconds left.
Lauri Markkanen, an All-Star last season, made five 3-pointers while recording 35 points and 12 rebounds. He is averaging 27 points and 11 rebounds.
The Jazz are expecting Markkanen to take another step upward this season. He set career highs in scoring average (25.6 points per game) and 3-point baskets (200) last season in his first campaign with the Jazz.