Nieminen, who last year became the first Finn to win an ATP title, will now face the winner of today's second semi-final between world number one Roger Federer and towering Croatian Ivo Karlovic.
The opening set between Nieminen and Baghdatis was an evenly balanced affair with neither player offering the other a single break point prior to the tie-break.
After an early exchange of minibreaks, Nieminen grabbed set point with a brilliantly executed stop volley and was then handed the set thanks to a Baghdatis double fault.
The 2006 Australian Open finalist rarely looked in contention after that, dropping his serve twice in the second set.
Nieminen stayed impressively focused, letting just four service points slip to secure his first place in a final this year.
REUTERS PDS RAI2018