Collison has started West Ham's last two Premier League games against Aston Villa and Norwich after returning from a successful loan spell at Bournemouth.
The midfield dynamo impressed during a month-long loan stay on the South Coast and he was quickly restored to the starting line-up by Sam Allardyce upon his return to Upton Park.
Collison is relishing the chance to stake his claims for a regular spot in Allardyce's side when Chelsea visit Upton Park on Saturday, and the Wales international is happy that the Hammers boss has shown faith in him since his return from a loan spell.
"It is great to be back in the fold and I am thankful to the manager for starting me in the last two games," Collison told Sky Sports.
"I really enjoyed my time at Bournemouth and I think it was perfect for me to get some games under my belt.
"That has helped me win my place back in the West Ham starting XI and I am determined to keep my spot in the team.
"I am happy with my form and fitness and it is up to me to prove to the manager that I deserve an extended run in the side.
"We face a massive test against Chelsea this weekend, but it is a game all the lads are really looking forward to as we enjoyed a great win over them last season."