SAN DIEGO (AP) — The San Diego Padres have promoted yet another prospect from the minor leagues, and this time it's the best one yet.The Padres selected the contract of 21-year-old Luis Urias, one of baseball's top prospects who is expected to be their second baseman of the future.Urias was set to bat second against Felix Hernandez in his big league debut in the opener of a two-game series against the Seattle Mariners on Tuesday night.Urias' promotion comes as the rebuilding Padres are on pace to lose 100 games for the first time since their infamous Fire Sale season of 1993.The Padres brought up Urias even though Triple-A El Paso has qualified for the Pacific Coast League playoffs."We felt like he'd done enough in the month of August," manager Andy Green said. "He played really, really well. He was kind of challenged at the beginning of the month to kind of step up his game because there was the belief he had more inside of him and he did a great job. He's a guy we've been talking about all year that the time would come, and when would the time be, and we got to the point where felt the time was now. It gives him the opportunity to play over a month in the big leagues the rest of the year."The arrival of Urias marks the beginning of another wave of talent coming from the prospect-rich farm system to the big league squad, which at 50-83 has the worst record in the NL.He hit .296 with a .398 on-base percentage with Triple-A El Paso. He hit eight homers and drove in 45 runs, with 67 walks and 109 strikeouts.Urias signed with the Padres as an international free agent in December 2013 when he was 16.His first call after the promotion was to his parents in Mexico."I always thought it would be a great feeling. It was something that I cannot explain right now," Urias said. "I was so happy, especially when I called my dad and my mom. That was a feeling that I will never forget."The Padres have one of worst offenses in the majors. Green knows bringing in one guy won't radically change the production."He's a guy we believe in," Green said. "We love his on-base skills. It's a good spot in the lineup. Just in general we've struggled to get on base, and he's always done that very well. Whether he starts off doing that well in the big leagues or it takes a little while, we believe he's going to do that very well for a long time.""I'm the player that I can get on base," Urias said. "I think that's my type of play, to put the ball in play and score a couple of runs."Green said Urias will also play some at shortstop.___More AP MLB: https://apnews.com/tag/MLB and https://twitter.com/AP_Sports