For whatever reason, sometimes I am only able to find one card of certain players. To be considered a One-Card Wonder, a player must have been active since 1991 (when I started paying attention).
I have discussed Brendan Donnelly briefly in the past here as a former replacement player. So that was already one strike against Donnelly for having more than a couple of cards. He also only spent one season with the Red Sox and was injured for a large portion of the year. So that does not help either. Donnelly's Red Sox career lasted all of 27 games and 20.2 innings.
Donnelly's only two Red Sox cards are from special sets. I only have the Red Sox gift set, so that is my only card of Donnelly.
Donnelly was acquired prior to the 2007 season in a trade with the Angels for minor leaguer Phil Seibel. He was brought in to shore up the bullpen a little bit, and he was successful for the short amount of time he was active. He pitched to an ERA of 3.05 with a 15/5 strikeouts/walks. Unfortunately, the injuries caught up to him and he did not make an appearance in the postseason.
The next year, Donnelly was one of the players whose name appeared in the Mitchell Report as being connected to performance enhancing drugs. Donnelly was allowed to leave as a free agent to the Indians.