The Pennsylvania Ballet will have one new principal dancer and a new structure for the ranks of its dancers when it opens its 2019-20 season in October, the company announced Tuesday.

Artistic director Angel Corella promoted Zecheng Liang to the principal spot vacated by Ian Hussey, who retired on Sunday.

Liang joined the company’s corps de ballet in the 2017-18 season and was promoted to soloist last year. He has danced principal roles in The Sleeping Beauty, Swan Lake, George Balanchine’s The Nutcracker, Theme and Variations, Jewels, and other ballets.

Liang was born in China and has won or placed at many international ballet competitions. He danced with the Houston Ballet before joining the Pennsylvania Ballet, an increasingly international company.

The new ranking method is a multi-tiered system more common in Europe than the United States, with the addition of a new first-soloist rank (between soloist and principal) and a new demi-soloist rank (between corps de ballet and soloist).

The additions are double-edged sword. There are more opportunities for dancers to move up in increments. On the other hand, the rank of principal is that much more of a climb.

Three soloists have been promoted to the new first-soloist rank. They are Yuka Iseda, who danced with Hussey in some of his final performances; Nayara Lopes; and Albert Gordon. All joined the company in the 2016-17 season. Iseda is from Japan and Lopes from Brazil. Gordon, from Virginia, danced with the Boston Ballet before moving to Philadelphia.

Kathryn Manger, Ashton Roxander, and Peter Weil have been promoted from the corps de ballet to soloist. All three are American. Weil is from Jenkintown and did much of his training at the Metropolitan Ballet Academy.

Six dancers were promoted to the new demi-soloist rank: Etienne Diaz, Sydney Dolan, Russell Ducker, Thays Golz, Alexandra Heier, and So Jung Shin.

Diaz is Cuban and engaged to principal dancer Mayara Piñeiro. Dolan was born in Philadelphia, raised in North Carolina, and won a 2018 Princess Grace Award. Ducker is British, Golz is Brazilian, Heier is from Boston, and Shin is from Korea.

Four apprentices have been hired to the main company as members of the corps de ballet, and three will join the company as apprentices from the Pennsylvania Ballet II.

In all, the 2019-20 main company will have 40 dancers, two more than last year, including eight principal dancers, three first soloists, seven soloists, six demi soloists, and 16 corps de ballet dancers.