Both players will be all the better for the game time under their belts as they continue to step up their fitness.
The home side had the better of the match, Watson and Cain both striking the woodwork in the first half before Jacob Blyth bundled a 70th minute corner home for the only goal of the game.
Rovers sub' Dean Rittenberg could have rescued a point with 14 minutes to go but his goalbound shot was tipped onto the post by Conrad Logan.
Eric Kinder was able to call upon seniors Dickson Etuhu, Adam Henley and Yann Songo'o for the match at the King Power Stadium. Etuhu making only his second appearance in over eight months for Rovers. Jordan Slew also returned after a long-term back injury for his first start since the summer.
On a chilly night in the east midlands it was Rovers who created the first opening of the game, John O'Sullivan taking advantage of the space afforded to him to shoot goalwards but Conrad Logan in the Leicester City goal made a comfortable save.
After that it was very much one way traffic towards David Raya's goal, Adam Dawson whistling a 10th minute effort past the post.
Just past the quarter hour and the Foxes really should have opened the scoring. After Harry Panayiotou had cut into the area from the right he teed up Michael Cain but from 12 yards his shot struck the crossbar.
Rovers couldn't clear their lines and immediately the ball fell to Ryan Watson and from even closer out he struck the identical part of the bar as the visitors breathed a sigh of relief.
On 19 minutes the home side again wasted an excellent chance. Adam Dawson's centre from the right was met first time by striker Jacob Blyth but he somehow fired over from close-range.
David Raya made a smart save to deny Blyth on 24 minutes before Watson hit wide from outside the box.
Rovers came out of their shell somewhat as the half drew to a close, the lively John O'Sullivan trying his luck from distance but his 35-yard effort was never going to trouble Logan.
The last action of the half saw a corner from the right that was met by the head of Dickson Etuhu but the ball struck a defender and bounced to safety.
The opening exchanges of the second period saw City the better going forward once more, dangerous cross from Dawson in the 54th minute saw Blyth dive full length to connect but his brave header flashed wide.
Jordan Slew came through just under an hour on his return to action, he was replaced in the 57th minute by Academy striker Dean Rittenberg.
Rovers had their first attempt at goal of the half moments later, after Darragh Lenihan had been fouled, Ryan Edwards took the resulting free-kick but his 25-yard blaster fizzed narrowly over.
A Raheem Hanley back-pass almost played in Harry Panayiotou moments later but Yann Songo'o got back with an important tackle.
Moments later and an excellent interception from Sean St. Ledger sent Panayiotou away once more, but he chose to shoot early and whilst there was plenty of power behind the effort it lacked the accuracy.
The 70th minute would prove to be a mixed one for young Rovers goalkeeper David Raya, a finger-tip save denied Panayiotou, but from the resulting Michael Cain corner, he failed to hold the ball under pressure and Jacob Blyth bundled the ball home for the opening goal of the game.
The home side went looking for a second and Cain was just over the angle with a well-struck shot from the edge of the area.
Then a great ball in from the right saw Blyth hunting his second, but as he flung himself towards the ball but he just couldn't connect as it flashed across the area.
However Rovers could have been level on 76 minutes as Dean Rittenberg fired goalwards only to see Conrad Logan touch his effort onto the foot of the post. Then a Hugo Fernandez free-kick threatened to sneak in until the Irishman claimed the ball.
Dickson Etuhu and Adam Henley both played the entire match as they continue their recovery from injury, the duo worked hard throughout as Rovers slipped to a narrow defeat.
LEICESTER: Logan (c), Sesay, Bakayogo, Watson, St. Ledger, Kennedy, Dawson (sub Stankevicius 89 mins), Cain, Panayiotou, Blyth (sub Elder 82 mins), Dodoo (sub Paratore 90+2 mins).
Subs not used: Pearson, Smith.
Goals: Blyth 70 mins.
ROVERS: Raya, Henley, Tumwa, Etuhu, Songo'o, Edwards, Fernandez, Lenihan, Slew (sub Rittenberg 57 mins), O'Sullivan (c), R. Hanley (sub Daniels 71 mins).
Subs not used: Urwin, Bauress, Daly.