SAN ANTONIO — Some details of Saturday night are still unclear.

Harrison Barnes subbed in for Victor Wembanyama with 11:07 remaining in the second quarter of the San Antonio Spurs' road win over the Dallas Mavericks. Wembanyama had played just 53 seconds of the period, missing his only field goal attempt.

While Wembanyama was out, the Mavericks embarked on a 12-4 run that prompted Johnson to reinsert his star with 7:12 remaining. Within the next three minutes, Wembanyama logged seven points, one block, one rebound and one assist. He looked motivated.

Wembanyama and Mitch Johnson had different stories of the interaction when asked about the peculiar change to the rotation. The Frenchman blamed a sideline miscommunication.

"I pointed at Mitch intensely," Wembanyama began, "because I was wondering what kind of defense we were in. And I think he understood that (as) I wanted a sub."

Johnson, who spoke first, didn't have a chance to address Wembanyama's explanation. His own account, however, suggested the substitution may have been more deliberate.

"I mean, it was a second night of back-to-back," Johnson said, "so, there was a little bit of mindful minutes ... (but) we've just all got to be better. We've got to make sure we're putting our energy into the right stuff ... we've got to play like our hair's on fire."

Whether Johnson intended to send Wembanyama a message remains unclear — he likely won't be asked about it again. But what isn't disputed is how the 7-foot-4 center responded after returning to the floor. That exemplified Johnson's broader intent on Saturday.

The Spurs earned their first win of the season over the depleted Mavericks, 122-106. Inside the visiting locker room at American Airlines Center, you wouldn't have known.

"If you were in there, you would have thought we lost the game," De'Aaron Fox said.

For a team coming off a 62-win season and an NBA Finals berth, a 1-2 start wasn't what the Spurs had envisioned for 2026-27. Neither was the manner in which they've played.

San Antonio opened its season with a convincing loss to the Oklahoma City Thunder before falling to the Houston Rockets in Austin three nights later after Wembanyama's final shot was blocked by Amen Thompson. Both games exposed growing pains associated with the Spurs' new three-guard starting lineup, featuring Fox, Stephon Castle and Dylan Harper.

Finding chemistry takes time. Johnson understands that. But some of San Antonio's early struggles have extended beyond unfamiliar rotations and offensive execution.

"Our floor right now is way too low," Johnson said.

The coach wasn't particularly interested in sugarcoating his assessment, either.

"Effort goes a long way," Johnson explained. "As simple as it sounds and as talented as these guys are, consistent effort with just a little bit of togetherness and execution can really be something to grow and build upon ... we just have not been consistent enough."

That inconsistency has become a central concern for Johnson amid San Antonio's slow start. The Spurs have shown flashes of the team that came within three victories of an NBA championship, but haven't sustained that level of play four months later. Fox agreed.

"We can say we have the experience," the veteran point guard said, "but it's a new season. And if we want to talk about that, we have to be able to go out there and back that up."

Fox continued: "I don't think anyone would say that we've played well. We have to get back to our standard. And until then, we have to look at ourselves in the mirror."

The Spurs saw evidence of Johnson's messaging. Once he called a timeout with 5:53 left in the second quarter — his squad, with Wembanyama back in, trailed by one point — he began harping on the lack of effort he was seeing. They responded appropriately.

"Once we were able to dig ourselves out of that," Fox said. "I don't mean dig ourselves out as far as the score. I mean ... out of the way that we were playing ... we were up double digits."

San Antonio carried a three-point lead into the fourth quarter and never trailed again. Wembanyama finished with a team-high 23 points while Fox, Harper and Castle combined for 60. Their ultimately one-sided victory didn't spare them from an "inspiring" postgame speech from Johnson, but it may have slightly softened the blow.

"Mitch was very purposeful in his speech," Wembanyama said. "Very strong."

For Wembanyama, the Spurs' early struggles are part of a larger process. While they work through the kinks of their new starting group, he's preaching an incremental approach.

"We have to trust the process and keep the big picture in mind," Wembanyama said. "We're building. Right now, it's what the regular season is for. We're building."

Asked if he feels the effort is lacking, Wembanyama noticeably differed from Johnson.

"Definitely not," Wembanyama said. "Other things (are issues), but not the effort."

While the Spurs work toward finding their identity, they want to ensure the habits that helped them reach the NBA Finals don't disappear in the process. In Johnson's words, they need to raise their floor, which has earned them a 1-2 record to begin the season.

"We have to try to replicate as much of last year as possible," Fox said, echoing his coach, "but we got to start doing that. And you want to do it sooner rather than later."

That includes holding one another accountable — something Fox believes Johnson has never been afraid to do. He enjoys having a coach willing to call out his players.

"He's going to talk to you," Fox said. "If you're not playing up to the standard that our coaching staff or your teammates or even yourself expects, he'll pull you."

Saturday night, that may or may not have included Wembanyama. Those details are foggy. But a noticeably amped-up Johnson spoke to reporters in a small interview room afterward.

He made sure one thing was crystal clear.

"We've just all got to be better," the coach said. "We've got to make sure we're putting our energy into the right stuff ... we've got to play like our hair's on fire."