Abstract: On September 8, 2010, in Tamraz v. Lincoln Electric Co., the U.S. Court of Appeals for the Sixth Circuit held that a neurologist’s expert testimony was speculative and therefore inadmissible under Rule 702 of the Federal Rules of Evidence. In so holding, the Sixth Circuit departed from its traditional deference to Rule 702 rulings of district court judges. This Comment argues that, although the Sixth Circuit’s decision is consistent with the requirements set forth by the 1993 U.S. Supreme Court decision Daubert v. Merrell Dow Pharmaceuticals, the Sixth Circuit opened the door to more aggressive review of Daubert rulings.