The Blues brought in James McCarthy and Gerard Deulofeu during the summer months, while Ross Barkley has established himself as an important member of squad this season, but Osman has revealed that he is pleased to see manager Roberto Martinez bolster the team.
"For the first time in a long while I found myself on the bench away at Aston Villa last week," Osman told the Daily Mail.
"We've now got a much bigger squad than we have ever had in the past and competition for places in the starting 11 is fierce.
"We are also at a period in football where teams don't win things anymore, squads do, so we're pleased with how the manager has strengthened."
The Blues are currently sixth in the Premier League.