The Dallas Mavericks had a chance to lock up a Western Conference playoff spot with a win Friday night, but couldn’t put away the Houston Rockets in a 153-149 overtime defeat.So Dallas will try to clinch a postseason berth Sunday night, and it could take the court at the Visa Athletic Center on Sunday already having done so if the Memphis Grizzlies lose their game earlier in the day.The Mavericks face the Phoenix Suns, who got seeding games off to a good start Friday with a 125-112 win over the Washington Wizards.The Mavericks (40-28) lamented losing a three-point lead on a free throw and tip-in of the missed second free throw with 3.3 seconds left in regulation against Houston. Coach Rick Carlisle said after the game that the loss was “about as tough as it gets, and it just comes down to basic execution.”Dallas got major production from its stars — a triple double from Luka Doncic with 28 points, 13 rebounds and 10 assists, and a dominant effort from Kristaps Porzingis with a season-high 39 points and 16 rebounds. Trey Burke added 31 points off the bench.”I think we can still work to be a better defensive team,” Carlisle said before accepting blame for the loss. “A lot of this stuff comes down to defense.”Fourth-quarter struggles have been an issue for the Mavericks this season, and Dallas has lost 17 games by five points or fewer. The Mavericks scored just 20 points in the fourth quarter against the Rockets and average 24.3 points in the last 12 minutes in their past three games, two before the league shut down due to the COVID-19 outbreak.The Mavericks will see a Suns team that scored 125 points Friday and had six players score in double figures. Phoenix is a longshot to get to a playoff or play-in series as the last team from the Western Conference to get to the re-start based on record, but the Suns are still alive.Center Deandre Ayton scored 24 points and grabbed 12 rebounds, and All-Star Devin Booker led the way with 27 points.Booker took it upon himself to be more aggressive and lead his team on offense and defense.”Some nights, it’s my job to be aggressive and get the flow of the offense moving,” he told the Arizona Republic. “That’s what I try to do every time I go out there.”Ayton, the first player taken in the 2018 NBA Draft, might have added a new dimension to his game. The 6-foot-11 center knocked down a pair of 3-pointers.”I’ve been working on this thing my whole life. I’ve been a good shooter,” Ayton told the Republic, adding that not shooting from long range as much is a result of him being comfortable in the system surrounding him on offense.Phoenix (27-39) is without forward Kelly Oubre Jr., who is practicing with the team but apparently not ready to play after knee surgery in early March. Oubre averages 18.7 points and 6.4 rebounds per game.