The under-21s followed their 2-1 win at Aldershot with victory by the same scoreline at Sutton, thanks to goals from Shane Nti and Ben Barclay.
But Ashley Nadesan’s 87th-mintue reply set up close to ten minutes, including stoppage time, in which Sutton launched a high-ball barrage at the Seagulls.
The late storm felt unnecessary for Albion but actually – in terms of player development – it was no bad thing.
It certainly a long way from Premier League 2.
Under-21s boss Ruth said: “We certainly made it hard for ourselves.
“I was very pleased with the team’s performance and I felt we deserved to be 2-0 ahead.
“From one ball, really, they get in, we have a loss of concentration for a second, and they make it 2-1.
“Then it becomes quite a test.
“Actually, when I look back at the game, I was able to see some real positive development from the young players.
“We don’t get that in our league. That pressure on our box, the direct play, the long throws, the corners and I thought the lads dealt with it so well.
“When they score out of the blue, it can knock you and, especially young players, they can find it hard to recover.
“I thought they recovered so well and stuck together and the subs who went on.
“So, from a development and coaching perspective, what the game gave us was a bit of everything and I thought the lads dealt with it really well.”
Albion gave Harry Howell, who has been with the first team squad this season, game time in a role to the right of midfield, quite advanced and quite wide but not as a winger.
He cut inside a couple of challenges to create Albion’s first real chance but fired over from the edge of the box.
Howell was rather closer on 21 minutes with a free-kick whipped over the wall and narrowly over the bar.
Nils Ramming held a close-range effort when Sutton threatened.
Sean Keogh was at left-back for the Seagulls although his forward raids meant it often looked like a back three of Noel Atom, skipper Freddie Simmonds and Barclay.
Joe Knight and Zane Albarus patrolled midfield with Nti leading the attack, Josh Robertson up with him and Nehemiah Oriola very wide on the right.
Ramming got down to save low shot from Brandon Njoku late in the first half but Albion took charge after the break.
Robertson had a shot blocked at close quarters, then Keogh could not pick out Nti in front of goal.
But they went in front with a very tidy finish from Nti on 66 minutes.
Found by Robertson’s pass, he guided the ball low into the corner with a confident one-touch finish.
Barclay added a header from a Howell corner eight minutes later following a nice move which saw the visitors work the ball to Oriola wide on the right.
But former Crawley striker Ashley Nadesan, sent on as a substitute, reduced arrears by converting a one-on-one after a long ball cleared Simmonds.
It was raining set-pieces from then on and Albion had to get through some gutsy defending as they challenged for high balls and threw themselves at shots.
But they stood up strong and had done enough to make it maximum points from two games.
Albion; Ramming; Barclay, Simmonds, Atom, Keogh (Silsby 76); Albarus, Knight; Howell (Belmont 76), Oriola (Mackley 84); Robertson, Nti. Subs not used: Jensen, Middleton, Kasvosve.