I have trained my dog's recall with play too. Similar to the way FLY30 discribes. Only I had a tugtoy with me. She has to come to me and stay with me to play that way.
Don't expect an overnight change

It takes a lot of work to get a great recall.
Try taking treats along on your walk, besides the bal or tug. And reward every time he looks at you, either with a treat or toy. That way you make yourself a great person to be with and in time, he will choose to come to you instead of that great distraction.
Here is the way I went about it.
Start in a save area(at home or in the backyard) Invite your dog to come play, by running away, showing your tug or ball.
As soon as your dog catches up with you, you throw a play party. Praise, cheer, play, just go nuts! I have a cue for this, besides my usual recall. Wen I say i'm gonnaaaa sssssssmooooke yaaaa, Jinx will break her play with another dog and come running to me. As soon as your dog does this consistantly in you distaction free area, you can start doing it outdoors, slowly building up the distractions.
Remenber that playing with other dogs is a huge reinforcement for a dog, while coming to you usually means they go on lead and leave.
So when you have your dog playing with another dog, just call him, play with him and then let him go do his thing again.
Then call, play, put him on lead and leave. Switch between the two, so you become unpredictable.
If you stick with it, you will get a great recall, but I have found it one of the most difficult things to teach my dog!!