With three low-pressure games remaining, Rick Carlisle would like to see a sharpened defense from his Dallas Mavericks before they open the playoffs. The Mavericks coach, however, is also trying to get his players some rest, and his team had a particularly taxing effort before Sunday night's visit to the Los Angeles Lakers. Dallas (48-31) is locked into the No. 7 spot in the Western Conference, but its defense has hardly been at playoff level. The Mavericks have allowed an average of 118.8 points while splitting their last six games and gave up 69 in the second half Friday while letting Denver take them deep into the night.