WASHINGTON -- Washington Nationals slugger Bryce Harper showed plenty of pop Thursday in his first on-field batting practice since undergoing ligament surgery on his left thumb last month. . "Honestly, we almost ran out of baseballs," manager Matt Williams said. "Between he and Wilson (Ramos), whoever gets in the park first today and goes to the outfield will have lots of souvenirs." Williams said Harper will begin a minor league rehab assignment after the Nationals begin a road trip next week. "Im still trying to see where my swings at. ... I dont see myself coming back after five games or four games," Harper said. "I really want to push it and see how I feel after eight, nine games down there. If I feel good before that, then Ill see where Im at." Williams will have to do some shuffling when Harper returns. Ryan Zimmerman, whose chronic shoulder problems have moved him off third base, has been playing in Harpers spot in left field. Williams originally said Zimmerman will move back to third, but now the manager says he will move players around depending on matchups and to give players rest. Zimmerman could be playing first base, third base or left field, while Harper will be used in all three outfield positions. Anthony Rendon will shuffle between second base and third base. "It doesnt really matter to me. I just want to play," Harper said. "I just want to be in the lineup and hopefully I can come back and help the team win." The Nationals have been playing well recently in Harpers absence, moving into first place in the NL East ahead of Thursdays opener of a four-game series against the Atlanta Braves. "One through nine, everyones swinging it really, really well right now. Were playing well. Im the odd man out, I guess," he joked. . Unfortunately for the Cleveland Cavaliers, James Harden was in the building. . The 49ers, 6-2 and riding a five-game winning streak following the bye week, also waived cornerback Nnamdi Asomugha and activated cornerback Eric Wright from the reserve/non-football injury list. Manningham made 42 receptions for 449 yards and one touchdown in 12 games and 10 starts last season before injuring his left knee in a loss at Seattle Dec. SONOMA, Calif. -- Tony Stewart was running lap times about a second faster than expected at Indianapolis Motor Speedway when a blown tire caused him to wreck this week in a Goodyear test. Goodyear officials said Stewarts accident 17 laps into Tuesdays 20-lap run was the only incident of the two-day test. The three-time NASCAR champion wasnt injured. "Our test speeds were extremely fast at Indianapolis," Greg Stucker, Goodyears director of racing, said in a statement Friday. "Tony was approaching the end of a very strong 20-lap run, with his lap times as much as a second faster than what has become the norm at Indianapolis at that point of a run. "It appears that increased, sustained speed over that run generated a significant amount of heat, which eventually caused the right-front to go down." Stewart wasnt upset with Goodyear over the incident, which he said "destroyed the car, so it was a good hit. "I am not really sure what the cause of it was, but thats part of tire testing," Stewart said. "Thats why you go to the test. Im sure theyll learn something from it and well go on." Joey Logano was one of six drivers at the test and said Stewart easily had the fastest car at Indy. Also at the test were Greg Biffle, Clint Bowyer, Kyle Busch and Ryan Newman, the defending race winner. Stewart, an Indiana native, has two BBrickyard victories and puts a huge emphasis on the July race. . Following Stewarts tire failure, Logano said Goodyear made adjustments "to figure out a way to knock some speed out of these race cars." Teams were given a different left side tire to use and will wait to see what Goodyear decides to bring for the race. "I know when we left they were going to go back and discuss where they wanted to be, but I think theyre going in the right direction on making sure they have the security in the tire, making sure its safe," Logano said. "Its definitely a very big challenge when you come to a race track and you go faster and youre already on edge. Youve got to come back with something thats even more durable and thats hard." Indianapolis has been a difficult track for Goodyear, and the tire brought to the 2008 race was not durable enough to make it more than a dozen or so laps. NASCAR was forced to call a caution roughly every 10 laps to force teams to change tires. "The thing about Indianapolis is the tough conditions the cars and the tires have to endure," Stucker said. "The surface is very abrasive, the long straightaways and short chutes are fast, cornering is tough with very little banking. Combine that with this new car package, and youve got conditions that put a lot of stress on the tires." ' ' '