The fullback completed a comeback to the Black Stars on Saturday, playing at right-back as the four-time African champions settled for a goalless draw with Uganda in 2018 World Cup qualifying.
Undoubtedly, the 26-year-old's return is due to a fine form at club level, having started and lasted for the full duration of five games on the bounce in the German Bundesliga.
“We’re obviously really pleased for Daniel, but this has been a collective effort from everyone who is involved with the team," Baum said about the Accra-born's reunion with Ghana's set-up as reported by the club's official website.
"Daniel recognised after his error against Middlesbrough in the preseason that he’s allowed to make them.
"But the most important thing is that he needs to learn from the experience.
"He’s shown that he has done that in the last five games, and he’s performed superbly.”
Opare's last game before his time out was against the USA in the 2014 World Cup group opener.
The absence has been due to a combination of injury and unstable club career.
Between the 2014 World Cup and this season, the defender has been on the books of four clubs, namely FC Porto, Besiktas, Augsburg and RC Lens, with whom he played on loan last campaign.
The former Real Madrid academy trainee is in line for his second Ghana appearance in three days as the Black Stars face Saudi Arabia in an international friendly on Tuesday.