For most of the last two weeks, the Cleveland Cavaliers and the San Antonio Spurs were the talk of the NBA. Now with their Finals series receding into memory, it’s time for them to catch up with the rest of the league. The other 28 teams have been in off-season mode for several weeks (and three-fifths of the Atlantic Division has been there for several months). By making the Finals, these teams have raised expectations for next year, since anything short of a title will count as a step back for both franchises. What will they have to do?

It seems counterintuitive since the city of San Antonio got to host a championship celebration and victory parade, but their Spurs face a much tougher challenge in the off-season. The Spurs were the best team in the Western Conference when judged by playoff result and by margin of victory, but their competition is very close behind. Fans of the Phoenix Suns can argue with some justification that the suspensions of Amare Stoudemire and Boris Diaw for Game 5 of the Spurs-Suns Western Conference semifinal were all that separated Phoenix from its first title. And three of the league’s five best teams are in the Southwest Division. Dallas could probably regress a tad and still be considered better than the Spurs, and if Houston’s top two players, Tracy McGrady and Yao Ming, stay healthy, then they too could be on equal footing with San Antonio.

The Spurs cannot afford to be complacent with such stiff competition, and they face another detrimental product of success, brain drain. Sam Presti, former assistant to general manager R.C. Buford has taken the Seattle GM job and he’s likely to bring a coach and some other front office personnel with him to the Pacific Northwest. On court the Spurs face another difficult foe: age. While their superstar trio, power forward Tim Duncan, and guards Manu Ginobili and Tony Parker are still in the primes of their careers, a good many of the role players are getting long in the tooth. Robert Horry turns 37 in August and the quality of his play (though not his hipchecks) is in steep decline; Bruce Bowen is 36, and Brent Barry is 35. Even some of the recent arrivals to the Spurs are on the wrong side of 30. Center Fabricio Oberto is 32 and his backup Francisco Elson is 31.

All of these guys are under contract for next season but not beyond that. With the Spurs right at the luxury tax threshold, it may behoove them to take one more shot with this unit and plan for major changes next summer. The Spurs will have a mid-level exception available to them though it’s hard to see any pressing dropoff in their oncourt performance. In terms of efficiency (points per 100 possessions), San Antonio was no. 2 defensively and no. 5 offensively. In the draft, the Spurs have the 28th and 58th selections, and given their draft history, I expect them to take a European league player that is barely on anyone’s radar, and a few years from now that player will be the next Ginobili (who was taken rather inconspicuously in the second round of the 1999 draft).

The Spurs have two underutilized assets at the end of their bench. Guard Beno Udrih has been a valuable reserve in the past, but this season his shot selection — if not his shot — seems to have deserted him, and he was played only sparingly, losing his spot in the rotation to ex-Net Jacques Vaughn. Also, former Knick Jackie Butler spent the season learning the San Antonio system. He’s signed longterm so I’d expect him to get more burn next season and begin the process of replacing either Oberto or Elson.

Although the Spurs have tough foes ahead, they should have just enough in the tank to use this offseason to build toward the summer of 2008, when the entire cast of role players will need to be replaced.

During the Finals, Cleveland missed a lot of open shots. Most folks figured it was the impact of the San Antonio defense, but avid Cleveland fans knew that it was a persistent problem that plagued their Cavaliers all season long. The Cavaliers were 22nd in the league in Effective Field Goal Percentage. That and an inability to get to the line, (a related problem, if opponents don’t fear your outside shooting, then they’ll just pack the lane and stop all drives to the hoop) dragged the Cleveland offense down this season. Cleveland excelled in the other two key factors of Offensive Efficiency, offensive rebounds (third in the league) and turnovers (ninth fewest).

So the Cavs’ off-season agenda is simple: Find folks who can shoot the rock. The Cavaliers payroll is also right at the luxury tax threshold (which means that the Cavs and Spurs combined to spend about $10 million less than the Knicks this season). There will be shooters on the market; in fact, if the Knicks opt to buy out Steve Francis, then the guard would fit in well in Cleveland. The Cavaliers have traded both of their picks in this draft, so all new personnel will come via free agency.

Cleveland has less daunting competition in its conference. Chicago could move up, and Detroit should stay strong. Otherwise, the Cavaliers will be potent contenders to return to the Finals, but without improved shooting, they figure to watch someone else get a trophy on their floor again.

mjohnson@nysun.com