Does a canoe (in a canoe race) that is drafting off a lead canoe, create a drag on the lead canoe?

I love to race outrigger canoes. I draft off of other canoes every chance I get.

Most paddlers don’t seem to mind but some complain that I’m creating a drag on their canoe even though I’m following 2 to 5 feet directly behind them. One guy dropped out of a race because I was drafting him. He later told me that I caused him to hurt his back. I told him that I’m sorry and I’ll never draft off him again.

I think that it is the mental pressure of having a competive canoe drafting that is what the lead canoe paddler is experiencing and not any physical drag.

When paddlers draft off of me, it just makes me I want to paddle faster and drop them. One time another paddler and I took turns leading and drafting. He said to me, “Let’s play leapfrog”. That was so much fun.

I can’t see how a canoe drafting off a lead canoe can cause a physical drag on the lead canoe. If you think that that is possible, then can you explain it me?