Rhodes, 21, was drafted into the squad for Friday night's friendly against Cyprus after an incredible burst of scoring that saw him hit 14 goals in six games, five of them for Scotland Under-21s.
Given that Scotland manager Craig Levein favours a 4-5-1 formation, competition among the forwards is fierce with Kenny Miller the undisputed favourite to start, although Mackail-Smith started both of Scotland's final two Euro 2012 qualifiers in the absence of the injured Cardiff striker.
Blackburn's David Goodwillie and Jamie Mackie, of QPR, are also with the squad in Limassol this week while Levein gave assurances that Ross McCormack was in his thoughts after scoring 10 times for Leeds this season.
Wolves striker Steven Fletcher could also come back into contention if he rebuilds bridges with Levein after pulling out of a squad in February by text message.
But Brighton striker Mackail-Smith is happy to have as many good forwards in contention as possible.
The 27-year-old hit 35 goals for Peterborough last season as they won promotion from npower League One and he is delighted to see Rhodes blaze a trail in the same division to give Levein another option.
"I'm not worried, I'm excited," said Mackail-Smith when asked about the impact of the 21-year-old Huddersfield forward's promotion.
"It's fantastic to have great competition. I think that's what everyone wants for the team, everyone wants the best players playing and good players competing to get into the team."
Mackail-Smith, who notched his first Scotland goal in the 1-0 win over Liechtenstein last month, added: "Jordan is a fantastic player, I've seen him play a lot last season and he has started this season fantastically, scoring goals for fun.
"It's a great time for him to come into the squad and hopefully be involved in the game."