Spanish rider Juan Pedro López of the Trek-Segafredo team maintained his 12-second lead over João Almeida in the overall standings as the three-week race approached the half-way stage. Romain Bardet is 14 seconds back.
In March, Girmay became the first rider from a sub-Saharan country to win a single-day classic when he triumphed in the Gent-Wevelgem race.
The first half of the 196-kilometre leg from Pescara to Jesi was mainly flat along the Adriatic coast before three fourth-category climbs later in the day.
Several riders attacked without success on the final climb to Monsano and the ensuing descent.
Girmay nearly missed a turn on the descent but was able to recover in time to rejoin the leaders for the finale.
Girmay started his sprint early and Van der Poel pulled even with him at one point. Then Girmay stepped up the pace and Van der Poel — realising he had no answer — flashed a thumbs up toward Girmay before the pair crossed the line. The Dutchman was also the first rider to give Girmay a congratulatory hug.
Girmay, who rides for the Intermarché-Wanty-Gobert Matériaux team, completed the stage in slightly more than 4 ½ hours. Van der Poel and Vincenzo Albanese crossed second and third, respectively, both with the same time as Girmay.
Stage 11 on Wednesday is an entirely flat 203-kilometre leg from Santarcangelo Di Romagna to Reggio Emilia that is linked to the production of parmesan cheese in the area.
The race ends May 29 in Verona.
