Answer
Sure, here's a short explanation: Elise Mertens has finished runner-up at two Grand Slam doubles tournaments during her career. She and her partner reached the finals of the 2018 US Open and the 2019 Wimbledon Championships, but were defeated in both matches, narrowly missing out on claiming the championship titles. These runner-up finishes are notable achievements, demonstrating Mertens' impressive performances and consistency at the highest level of professional doubles tennis.