history: My co-worker helped me with my part of the project which otherwise i would not have met the deadline without his help
current: I had a deadline coming for my part on the project. Without my co-worker's help, i would not have finished it on time. Very thankful to him
next: Its always great when u have good co-workers you work with.  Im glad you got it done on time!  What kind of project is it may I ask?