When Sean Lyons joined Havas in 2013 to oversee digital, he interrupted a decade-long run at R/GA. Now he's returning to the Interpublic Group of Cos' digital agency giant as president of the U.S. region.

Prior to joining Havas as global chief digital officer, Mr. Lyons served as senior VP-operations and business planning at R/GA; before that he managed the global Nike account across the network. During his time at R/GA he had a hand in the building of big, scalable platforms such as NikeiD and Nike+.

Mr. Lyons replaces Seth Solomons, who joined R/GA in 2013 as a managing director in New York, and was promoted to U.S. president earlier this summer. Mr. Solomons recently left the shop.

"We are very happy to welcome Sean back to R/GA as President, R/GA US," said CEO Bob Greenberg in a statement. "Sean's deep understanding of our culture, history of success at R/GA, and the global experience he gained during his two years at Havas make him the perfect person to lead our U.S. offices."

Andrew Benett, global CEO of Havas Creative Group and Havas Worldwide, said, "Through his strong leadership and an ability to foster unified teams, Sean helped drive innovation in our business and our work. We are grateful for his contribution over the past two years and extend our good wishes on his next venture."