Berdych, seeded sixth, defeated third-seeded Andy Murray 6-7 (4-7), 6-2, 6-3 and moved into Saturday's semifinals against world No. 1 Novak Djokovic. Simon, the No. 9 seed, ousted fourth-seeded Jo-Wilfried Tsonga 7-5, 6-4 and will face No. 2-ranked Rafael Nadal, who is looking for an eighth consecutive Monte Carlo Masters title, in the next round.
Berdych faced just one break point against Murray while winning 5-of-16 break opportunities. Even though he lost his serve once, Berdych won 72 percent of the points on serve.
Simon also had five breaks versus Tsonga. He had two in building a 3-0 lead in the first set and added another in the 11th game of the first set. He fell behind 0-3 in the second but won six of the last seven games to advance.
Nadal notched his 40th consecutive match victory at the event with a 7-5, 6-4 decision over Stanislas Wawrinka. Nadal took 74 percent of the points when serving.
Djokovic defeated Robin Haase 6-4, 6-2 despite having his serve broken four times. However, he finished with seven breaks in the nine games Haase served.