Caoimhin Kelleher is the latest player to be drafted into the Republic of Ireland squad ahead of the UEFA Nations League opener in Sofia.
The Liverpool goalkeeper replaces the injured Kieran O'Hara. Kelleher had been included originally in Jim Crawford's U21 get-together.
Seani Maguire and Dara O'Shea have joined Stephen Kenny's panel in recent days, while Troy Parrott missed out through injury.
Stephen Kenny took Ireland training for the first time on Monday, ahead of Thursday's game away to Bulgaria.
The former Dundalk boss appeared enthusiastic and energetic as he got to know his new troops.
Kenny will be the fourth different Republic of Ireland manager that first-choice keeper Darren Randolph has played under.
The West Ham man was among the first to face the media on day 1 of the Kenny Era, and explained what the new boss wants from his side, "Putting it simply, he probably wants to be a possession-based team.
"He wants us to show off probably more of our talent and ability. Be brave on the ball."
Randolph says Kenny will want the team to build out from the back.
"I think he just wants to be a bit more creative," the keeper added, "And use the players that we have in positions that he sees fit for them to perform best in."
There may be more of an emphasis on playing football than under the last generation of Irish managers, but Randolph expects that ease-on-the-eye to be tempered by common sense, "By me saying we're going to play out from the back, I think some of your colleagues or the public think we're going to start playing like Barcelona and Man City.
"Yeah we want to play, but we're not going to be taking stupid risks in international football with stuff to play for.
"Yes we want to be a possession-based team, and we're going to try different things, but there won't be anything ridiculous.
"But there'll be a slight change in what people are used to seeing."
While Randolph admits they'd prefer more time to get used to Kenny's methods ahead of the trip to Sofia, the 33-year old says they'll provide ample preparation for the real focus of the autumn - the Euro 2020 playoff with Slovakia.
A meeting was held between the staff and players on Sunday night where it was conveyed, "what he obviously expects, and what he believes we can achieve as a group, and the belief he actually has in us in what we can do going forward."