Christinna Pedersen
In January, Polii and Apriyani Rahayu began the season by finishing as runners-up in the Indonesia Masters, losing to second seeded Misaki Matsutomo and Ayaka Takahashi in the final. A month later, the duo played as the third seeds in the India Open and won the title after beating the first-seeded Christinna Pedersen and Kamilla Rytter Juhl in the semi-finals, and the second-seeded Jongkolphan Kititharakul and Rawinda Prajongjai in the final. She featured in the Indonesian women's team that won bronze at the Asia Team Championships held in Alor Setar and were quarter-finalists in the Uber Cup in Bangkok. In July, she and her partner lost in the quarter-finals of the Indonesia Open to Yuki Fukushima and Sayaka Hirota, but a week later, she won her third Thailand Open title, as she and Rahayu defended the title they had won in Thailand the previous year, when the event was known as the Grand Prix. In August, the duo won the bronze medal at the World Championships in Nanjing, and further bronze medals at the Asian Games in the women's doubles and team events. In the remainder of the 2018 tour, she and Rahayu only reached the semi-finals in Japan, China, Denmark, French, Hong Kong, and quarter-finals in the Fuzhou China Open. The duo achieved their career high as world number 3 in the BWF rankings in September.