LINQ and Entity Framework errors

I have two tables in SQL database:

Challenger (ChallengerID, FirstName, LastName, Email)
Rank (RankID, ChallengerID, Best, DateAcheieved)

 and using entity framework to access data. When I am trying to select columns from both tables i always get an error. What am I doing wrong? Thank you

Dim db As New MemoryGameEntities
Dim query = From t1 In db.Challengers
                        From t2 In db.Ranks
                        Where t1.ChallengerID = t2.ChallengerID And t2.Best = 1
                        Select (t1.ChallengerID, t1.FirstName, t1.LastName, t1.Email, t2.DateAchieved)