I, Alberto Merolio, whipped an American baseball player (9,6)

I believe the answer is:

baltimore oriole

I'm a little stuck... Click here to teach me more about this clue!

'an american baseball player' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.

'i alberto merolio whipped' is the wordplay.
'whipped' is an anagram indicator.
'i'+'alberto'+'merolio'='ialbertomerolio'
'ialbertomerolio' anagrammed gives 'BALTIMORE ORIOLE'.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.