Roma no relation UEFA Cup
Matthäus and Bayern teammate Andreas Brehme signed with Inter Milan of Serie A in 1988, winning the Scudetto in 1988–89 during their first season, and the Italian Supercup that year as well. Matthäus continued to enjoy further success with Inter, winning the UEFA Cup in 1991 and being named FIFA World Player of the Year. In the final, he scored a penalty in the first leg to help them to their victory over Roma.
Returning to Bayern Munich in 1992, he won four Bundesliga titles, two DFB-Pokals, another UEFA Cup and reached a second European Cup final in 1999. The only major club football honour which eluded Matthäus, for competitions in which he played, was the UEFA Champions League. Famously, he came within two minutes of picking up a winners' medal in 1999, only to have his hopes dashed by Manchester United, who scored two last-minute goals in the final, after he was substituted in the 80th minute of play while the team was still leading 1–0. When the two teams went to collect their medals Matthäus removed his runners-up medal immediately after he received it – it was the second time he had been on the losing side in a final under similar circumstances; in the 1987 final, Bayern had been leading 1–0 most of the game until two late goals gave FC Porto the win. After Matthäus retired, Bayern would win the Champions League in 2000–01 and later that year the Intercontinental Cup. His last official match for Bayern took place in Munich on 8 March 2000 and was a Champions League match against Real Madrid, which Bayern won 4–1.
During the 1999–2000 season, Matthäus moved from Bayern to New York City's MetroStars team of Major League Soccer in the United States. He played in the US from March to October 2000 and retired from professional football afterwards. During his season with the MetroStars, he traveled to St. Tropez when he was supposed to be rehabbing his back.Matthäus came out of retirement in 2018, at age 57, to play 50 minutes of 1. FC Herzogenaurach's final league game of the season. The team had already secured the league title, and the appearance allowed Matthäus to satisfy his ambition retiring with the club where his career started: "It was always my dream to play my last competitive game here."