In 1999, Speed (plaintiff) hurt his foot at a Sports Authority store and hired Scott Zahler to represent him. The client agreement stated that Zahler would represent Speed in any claims Speed may have “against Sports Authority, and any other Defendants later named or identified as a result of” the incident at Sports Authority. In 2002, Speed was treated for deep venous thrombosis in his leg by Dr. Muhanna (defendant). After the treatment, Zahler contacted Muhanna, seeking to depose him for purposes of Speed’s suit against Sports Authority. Muhanna was hesitant to give a deposition. Thus, at Muhanna’s request, Zahler sent him a letter stating the following: “This is not a medical malpractice case and neither now or [sic] in the future will you be subject to any type of malpractice claim.” Upon receiving the letter, Muhanna agreed to be deposed by Zahler. In 2004, using a different attorney, Speed brought a medical malpractice suit against Muhanna for the deep venous thrombosis treatment. The trial court granted Muhanna summary judgment on account of Zahler’s letter. Speed appealed.