A little over a month ago, the New Orleans Pelicans had the best record in the Western Conference.

Flash forward to late January and a six-week rough stretch has dropped them to fourth place, while the new No. 1 -- the surging Denver Nuggets -- are set to visit New Orleans on Tuesday.

The Nuggets saw their nine-game winning streak end with a 101-99 home loss to Oklahoma City on Sunday night.

Denver played its second consecutive game without two-time reigning MVP Nikola Jokic, who has tightness in his left hamstring.

It's unclear if Jokic will play Tuesday, but acting head coach David Adelman he expects his star to return "very soon." The offense is a shell of itself without him.

"I think it's much easier to switch one-through-five with us," Adelman said. "When Nikola is on the floor, it's virtually impossible to do that and it's virtually impossible to zone us. (The Thunder) did those two things and they're smart things to do."

Denver forward Michael Porter Jr. also missed the game against Oklahoma City for "personal reasons."

In the absence of Jokic and Porter, Jamal Murray became the primary scorer and responded with a team-high 26 points and nine assists.

"They doubled me," Murray said. "We kind of expected that. ... We prepared for it. We got what we wanted. We didn't finish like you're accustomed to seeing us finish. That's just on us. That hurts, knowing we did everything we could, and we didn't get over the hump."

The Pelicans have had trouble getting over the hump during a losing streak that matched a season-worst four games with a 100-96 loss at Miami on Sunday.

The Pelicans' offense has been outscored in the fourth quarter of each game during the streak and they took a lead into the final quarter in three of those games.

In those fourth quarters, they were outscored 31-24 on Sunday, 35-19 at Orlando on Friday and 35-22 in a loss at Cleveland that started the slide.

The only game during the losing streak in which they didn't lead through quarters was a 124-98 loss to the Heat last week in their most lopsided loss of the season. Even with most Heat starters sitting out much of the fourth quarter, the Pelicans were outscored 26-22.

The loss on Sunday came after New Orleans led by as many as 16 points. It hurt itself with 25 turnovers.

"Guys played at a high level, executed at a high level at both ends of the floor," Pelicans coach Willie Green said. "We came up short and we just have to take care of the basketball."

New Orleans has lost nine of its last 12 games and is starting to show the wear of not having leading scorer Zion Williamson (hamstring) for the last three weeks. It has not had second-leading scorer Brandon Ingram since late November.

"This is the tough part of the season," said Pelicans backup center Larry Nance Jr., who scored 12 points in Sunday's loss. "But no one feels bad for us. We don't feel bad for us. This is a strong locker room."

The Pelicans overcame a 14-point first-quarter deficit to defeat the Nuggets 121-106 on Dec. 4 at New Orleans. The season series will conclude with games at Denver on Jan. 31 and March 30.