United headed to Stevenage looking to build on last weekend's dramatic win over Bury with everything still to play for at what is a crucial stage of the season
Injuries to Jamie Devitt [Hamstring] and Kelvin Etuhu [ankle] ruled them out and that meant a place on the bench for youth first year Jarrad Branthwaite and second year academy prospect Keighran Kerr.
Defender Gary Liddle was handed the captain's armband as striker Hallam Hope took to the field to make his 200th career appearance.
An early Boro free kick caused problems as Guthrie got a flick inside the area. It looped high, and Cuthbert reacted quickly to help it on its way. His touch was heavy and the ball dropped beyond the front post.
Another long ball into the area found Guthrie on the move and his downward header fell for Sonupe to strike. It bounced awkwardly and Collin was able to gather it in.
Carlisle mounted a good attack in response as Miller and Scougall combined to work a way through the midfield area. Thomas took over, and his low pass invited a shot from Simpson. Farman was beaten, but it was always heading wide.
Another shot from Sonupe was carefully dealt with by Collin as it came low through bodies, and the United stopper was there again to deal with relatively tame efforts from Guthrie and Chair as they tried their luck from distance.
But it was disaster for the Cumbrians when they were carved open through the middle with just 17 minutes on the clock. Guthrie and Chair were involved, but it was Iontton who took the honours as he overlapped before steaming into the box. Collin had no chance as a firm finish rattled into the net.
A training ground corner routine saw Chair ghost into the box as the delivery dropped to his unmarked position, with Boro still on the front foot. He tried to cushion his volley but it had too much on it and it angled over the bar.
United had a real chance to pull level when Hope overlapped to take a ball from Slater. He kept it in as he raced towards the corner flag then delivered a beauty of a cross. Thomas was in space but he misjudged it and it spun harmlessly away as it skimmed off his forehead.
The confident Ilias Chair tried his luck from distance with just two minutes on the second half clock, but Collin stood his ground to take it into his hands as it bounced up in front of him.
Carlisle responded in kind with a well-worked move as Thomas beat his man and angled at the box. Hope took over, and a reverse pass from him sent O'Hare clear. He appeared to be clipped as he took his shot but the referee ignored the vociferous penalty appeals.
Things opened up and Chair hit the post with a bobbling effort which caught the United back line by surprise. The rebound was recycled quickly and Guthrie spun to send a rifled effort at the roof of the net. Collin reacted well to tip it over.
But the visitors were undone from the resulting corner as Guthrie ran off his man. The big forward had time on his side and calmly picked his spot with an accurate header.
A fizzed effort from Tom Parkes was an inch away from bringing the Blues back into it as he sent one across the face of goal, but the afternoon got even worse just past the hour when O'Hare was judged to have pushed Guthrie to the floor inside the box. The referee took an age to make his decision, but it was Guthrie who dusted himself off to sweep the spot kick past Collin.
The game settled down as Stevenage closed tight, but Kennedy had half a sight when he made a run into the area. His header had Farman interested but it skipped past the upright.
A late shot from Thomas was deflected behind for a corner, and his deep delivery was put back into the mix by Hope. Boro shut the door once again and the moment was cleared.
Hope was next to try his luck, as Carlisle pushed to get something from the game, but it took a deflection and was easy for Farman to smother.
Stevenage - Iontton (17), Guthrie (52 & 62 pen)
Carlisle United - Miller (30), Parkes (89
Stevenage - Farman, James-Wildin, Timlin, Cuthbert, Sonupe (Newton 78), Chair (McKee 74), Vancooten, Iontton (Byrom 88), Guthrie, Nugent, Martin. Subs - Byrne, Hunt, Byrom, Revell, Gibson.
Carlisle United - Collin, Miller, Liddle, Grant, Parkes, Scougall, Slater (Glendon 54), O'Hare, Thomas, Simpson (Kennedy 54), Hope. Subs - Gray, Gerrard, Gillesphey, Branthwaite, Kerr.
Referee - Mr Carl Boyeson
Attendance - 2,770 (416 away fans)