Markkanen scored 23 points and connected on 5 of 8 3-pointers to lead Chicago to a 113-94 win over the Washington Wizards on Sunday.
Bobby Portis had 18 points and hit 4 of 5 from long range, and Sean Kilpatrick added 14 points. The Bulls shot 52.4 percent overall from the floor and were 18-for-34 on 3s -- matching their season high -- as Hoiberg missed the game with an upper-respiratory infection.
Hoiberg left United Center before tipoff, leaving associate head coach Jim Boylen to direct Chicago to its second straight win following a seven-game skid.
"I thought we were focused from the start," Boylen said. "We talked about a first-quarter edge. I thought we had it."
The Bulls sizzled early against the playoff-bound Wizards, who rested five-time All-Star John Wall.
Chicago shot 60.9 percent in the quarter and connected on 8 of 11 3-point attempts, with Markkanen and Portis each sinking three from long range.
Markkanen nailed his first 3 just over three minutes in to set an early rhythm.
"Of course it helps when you make the first one, but I always think it's going in," said the 20-year-old Finn. "Just trying to take my normal shots and today they were falling a little bit better."
"We ran a couple of things for him early just to get him to his spots where he can score and make plays," Boylen added.
The Bulls kept connecting. Chicago upped its field-goal percentage to 64.3 and went 11-for-17 on 3s in the first half. Markkanen led with 15 points and four 3-pointers at the break and Chicago ahead 68-59.
Wall remained on the bench against Chicago after playing 33 minutes in his first game in over two months on Saturday. The slick point guard had 15 points and 14 assists in the Wizards' playoff-clinching 107-93 win over Charlotte.
Before Saturday, Wall had last played on Jan. 25, six days before he underwent left knee surgery. The Wizards went 15-12 during that absence and they were flat on Sunday without their high-tempo star whom coach Scott Brooks called his team's "Ferrari."
"We made the playoffs, but are we just excited about making the playoffs?" Brooks said. "That's the question we have to ask.
"We weren't ready mentally. When you're not ready mentally you're not going to have a chance to win and that was the game tonight. They were just running their offense and we were chasing them around with no purpose."
The Bulls opened a 15-point lead late in the first quarter before Washington finished the frame with a 6-0 run to cut it to 36-27. Getting a lift from Scott and others off their bench, the Wizards trimmed the Bulls' lead to four points three times in the second quarter.
The Bulls maintained their hot shooting pace throughout first half before cooling down in the second.
"They came out and just shot 3s," Beal said. "That's pretty much all they did. For the most part, we couldn't guard the 3-point line."
Chicago then effectively managed its lead -- and used all but one bench player -- before pulling away late.
NOT THE FIRST TIME
Boylen stepped in as a head coach once before, taking over for Gregg Popovich with San Antonio on Jan. 17, 2014, after Popovich was ejected in a loss to Portland.
"That's different than Fred calling me at 9 (a.m.), saying, `I think I'm struggling. You've got to be ready," Boylen said.
Boylen admitted he had fun coaching, but added, "I feel bad for Fred. I've never seen him this sick before."
Wizards: Brooks said Wall "felt pretty good" on Sunday, but plans for how to use the star in Washington's final five regular-season games haven't been finalized. Washington plays two back-to-back sets down the stretch. ... F Markieff Morris started on Sunday after leaving Saturday's game with flu-like symptoms after nine minutes.
Bulls: G Zach LaVine (left knee tendinitis) and G Kris Dunn (right toe sprain) both missed their ninth straight games. Hoiberg, who met with reporters before the game despite being ill, said their status is day-to-day. ... G Antonio Blakeney (left wrist fracture) and F Paul Zipser (left foot pain) also were inactive. ... Robin Lopez was back in the lineup, starting at center on his 30th birthday, after sitting out Friday's 90-82 win in Orlando. Lopez was fined $25,000 for yelling at officials and failing to leave the court quickly after he was ejected in the fourth quarter of Chicago's loss at Miami on Thursday.
Wizards: Visit Houston on Tuesday in the second game of a three-game trip.
Bulls: Host Charlotte on Tuesday.
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