Summarize and humanize this content to 2000 words in 6 paragraphs in EnglishThe San Diego Padres have agreed to a nine-year, $135 million contract extension with center fielder Jackson Merrill, a league source confirmed, keeping one of baseball’s best young players for the long term just six games into his second major-league season.Merrill, 21, was San Diego’s first-round pick in 2021 and enjoyed a breakout rookie season in 2024, slashing .292/.326/.500 with 24 home runs and 16 stolen bases in 156 games. For that, he earned an All-Star selection and Silver Slugger award and finished second to Paul Skenes in NL Rookie of the Year voting.Merrill has contributed plenty to the Padres’ 6-0 start this season, batting .400 (8-for-20) with one home run and six RBIs.Robert Murray of FanSided first reported Merrill’s extension.This story will be updated. More to come.(Photo: Orlando Ramirez / Getty Images)