At 7, Red Falx retains a commanding presence in Japan’s turf-sprint division. Last October, Red Falx won the Grade 1 Sprinters’ Stakes at Nakayama Racecourse. On Sunday, Red Falx will be favored to win the first Grade 1 race of the 2018 Japanese season in the $2.053 million Takamatsunomiya Kinen at Chuyko Racecourse. Red Falx has won 10 of 25 starts but was beaten in his first start of 2018, a third in the Grade 3 Hankyu Hai at seven furlongs at Hanshin Racecourse on Feb. 25. Trained by Tomohito Ozaki, Red Falx was third in the 2017 Takamatsunomiya Kinen to Seuin Kosei, who is part of Sunday’s field but is rated an outsider. Seuin Kosei is winless in five starts since last year’s win in this race. A more logical threat to Red Falx may be Let’s Go Donki, a 6-year-old mare who was second in the 2017 Takamatsunomiya Kinen and the Sprinters’ Stakes but only fifth in the Grade 2 February Stakes at a mile on dirt at Tokyo Racecourse on Feb. 25. The race drew a field of 18, the maximum number of runners allowed in Japan, and has one American-bred: Rieno Tesoro, a 4-year-old filly by Speightstown. A New York-bred filly, Rieno Tesoro was purchased for $250,000 as a yearling in 2015. She was second in the Grade 1 NHK Mile on turf last May. Her recent form is not as encouraging. Rieno Tesoro was 10th in the Grade 3 Ocean Stakes at Nakayama Racecourse on March 3.