The NBA Most Improved Player of the Year (MIP) award is often overlooked by basketball fans. For teams, though, having a breakout star will always be a thrilling surprise. Last season, Lauri Markkanen put on a stunning performance after he was traded by the Cleveland Cavaliers to the Utah Jazz. He earned his first All-Star selection and won the MIP by season’s end.Leading into this season, Mikal Bridges was a big favorite to win the George Mikan Trophy. He had a spectacular 27-game run for the Brooklyn Nets following his trade from the Phoenix Suns. Bridges, though, is off to a slow start.There are emerging talents who could sustain their form and challenge for the NBA Most Improved Player of the Year award. In the first nine days of the new season, a few have been unexpectedly pleasant surprises for basketball fans.Players who could challenge for NBA Most Improved Player of the Year awardHere are the top five:#5 Devin VassellVictor Wembanyama is the biggest draw every time the San Antonio Spurs play. The highly-touted rookie is the favorite to win the NBA Rookie of the Year award. Many are expecting to watch never-before-seen action coming from the French phenom.Meanwhile, Vassell has steadily been the Spurs’ best scorer, hitting a career-high 20.0 points in four games. Last season, his scoring jumped from 12.3 PPG to 18.5 PPG, but he played just 32 games. The shooting guard's impact isn’t just on offense. He's also one of San Antonio’s best defenders.If he keeps that up, he could be one of the contenders for the NBA Most Improved Player award.#4 Grant WilliamsGrant Williams and the Boston Celtics couldn’t agree a new deal. The forward reportedly wanted $20 million per season, which the Celtics didn’t want to part with. He was eventually sent to the Dallas Mavericks in a three-team deal.With Luka Doncic and Kyrie Irving around him, Williams’ scoring has spiked from 8.1 PPG to 15.5 PPG. He's hitting 54.3% of his shots, including a sizzling 55.2% clip from the deep.The Mavericks wanted Grant Williams for his defense, toughness and big-game experience. He could end up challenging for the NBA Most Improved Player of the Year award with how he has been playing.