SAN ANTONIO -- It's absurd to suggest that the Boston Celtics have benefited in any way from the groin injury that will sideline Isaiah Thomas for a fourth straight game on Wednesday night against the San Antonio Spurs.

But if Celtics fans are looking for the tiniest of long-term silver linings there is this: Thomas' absence has generated extra playing time for youngsters Terry Rozier and Jaylen Brown and the progress that pair has shown is one of the reasons that coach Brad Stevens remains encouraged by the direction of his team.

Isaiah Thomas' injury has allowed rookie Jaylen Brown to see more quality minutes for the Celtics. Kim Klement/USA TODAY Sports

The much-hyped Celtics have slipped to sixth place in a crowded Eastern Conference. Their lack of a signature victory and three gut-punch losses to a trio of quality opponents in a seven-day span last week left players frustrated because their improvements have yet to translate to wins.

After arriving in San Antonio on Monday, Stevens gave his team a rest and recovery day. The Celtics are staying at a sprawling resort 20 miles north of San Antonio and players gleefully took advantage of the amenities like ping-pong tables, a pair of golf courses, a water park, and a lazy-river pool. That helped them forget their struggles (as well as the season's first snow falling back home).

When the Celtics huddled Tuesday for a rare off-day workout at Antioch Baptist Church, any lingering disappointment from Sunday's near-miss in Oklahoma City seemed to have dissipated. When Stevens was asked about the progress of the rookie Brown, he went out of his way to stress that he's encouraged by the progress of this team as a whole.

"I feel really good about [the young] guys and their improvement," Stevens said. "And I feel good about the way we've played for the most part. I'm frustrated, certainly, by the results, but I'm excited about the way we're playing and I think we're in a much better place than we were a month ago."

Little more than a month ago, the Celtics were 3-3, owned the worst defensive rating in the league, and were reeling after getting their doors blown off in consecutive games against the Nuggets and Wizards (those two teams that are now a combined 18-30). Boston's 10-8 record since then is not exactly anything to write home about but a closer inspection of the team's numbers since then is a bit more encouraging:

What a difference a month makes A look at where Boston ranked in key statistical categories through Nov. 10 (then) versus the 18 games since (now): STAT THEN NOW Offensive Rating 109.0 (3rd) 105.5 (9th) Defensive Rating 112.3 (30th) 101.2 (5th) Net Rating -3.3 (20th) +4.3 (8th) Rebound % 45.3 (30th) 48.8 (25th) Record 3-3 10-8

The Celtics still have plenty of work to do to repair their defensive rating after an abysmal start. But the fact that Boston has played the past month as a team that ranks in the top 10 for both offensive and defensive rating is an encouraging sign for their long-term success. At some point, the narrow games that have gone against them should tip in their favor more often.

Only four teams in the NBA currently reside in the top 10 for efficiency on both sides of the ball. Those four teams -- the Spurs, Clippers, Utah Jazz, and Warriors -- own a combined record of 74-26 (.740) this season. The law of averages suggests that, if Boston plays the way it has the past month, its record will eventually improve.

The Celtics are hopeful to get Thomas back on Friday when they host the Charlotte Hornets. That won't help them Wednesday when they face a Spurs team that has won 10 straight meetings between the teams, including all seven tilts since Brad Stevens took over in 2013.

Boston needs players to step up in Thomas' absence to compete with the Spurs. Despite a bit of a late-November slump, Brown has been excellent in December, including being a crunch-time presence in recent games. Brown scored 10 fourth-quarter points before Boston fell to the Oklahoma City Thunder on Sunday.

For a Boston team that needs Brown's size behind Jae Crowder at the small forward position, it's a positive that Stevens is regaining his trust in Brown.

"I've been really encouraged by Jaylen's play the last four games," Stevens said. "Like anybody else his age, there's going to be moments of good and bad. He comes to work every day, he's trying to get better and, we've talked about it before, that body is important in this league, to be able to defend, to be able to rebound, to be able to create an advantage on offense. And we saw when Jae was out [with an ankle injury]. That's why Jaylen's continued improvement is critical."

Over the past three games without Thomas, Brown has averaged 10 points on 63.2 percent shooting. Brown is plus-15 in that span.

"I feel like the more I play, the more experience I gain, the better I get," said Brown, the No. 3 pick in June's draft. "That's how I feel. As I get more games under my belt, I feel more comfortable on the floor. This is how things work in the NBA. You just gotta try to keep learning and keep getting better."

Crowder has stayed in Brown's ear about staying consistent on the court.

"It's called the NBA, you're not going to play well every night," Crowder said. "You're going to have ups and downs. But you gotta stay the course and keep working.

"[Brown] expects himself to do good each and every night, and that's just not the way the NBA works. It's a long season, you have to stay the course, and keep doing the same things to get better. And not get too down on yourself."

That sounds like a good lesson for the Celtics as a whole.