THE spy in the stand has become old hat these days but it does show how seriously Leicester Tigers are taking their match against Glasgow Warriors in the European Champions Cup on Friday that one of the English club's coaching team was lurking in the terraces at Stadio Lanfranchi in Parma over the weekend.

Whether he and the money men at the club still think the fare was worth it is debatable. Clearly Gregor Townsend, the Glasgow Warriors head coach, did not want to show his hand in front of prying eyes and on that score he succeeded.

All the criticism of a final-quarter collapse that allowed the Italians to come from 30-11 down to threaten an improbable win, has to be taken alongside the knowledge that Townsend had chosen to rest as many frontline players as he could and then flooded the field with even an even younger and more inexperienced group once it looked as if the job was done.

He admitted later that he had probably got that decision wrong, but when it comes to concealing strengths, weaknesses and tactics from the Leicester spy, it could not have been executed better.

They did get the bonus-point win, despite the late scare; some of the players the club will rely on in years to come were given a chance to prove their mettle in the heat of an intensely physical battle, and the manner in which so many second-, third- and even fourth-choice players handled the ball so adroitly and attacked so willingly in the first 53 minutes must have given even Leicester a few moments' thought.

As the club's most experienced player, Sean Lamont has seen it all before. For him, this season has to be all about breaking Glasgow's European duck and even though he scored two of their four tries, he was far from happy with some the team's performance.

"It was far from pretty and far from the standard we want to set. If we play like that against Leicester, we will get torn apart, and we know that. We got a win and a bonus point, but you could tell from the mood in the changing room that we were far from happy with that result," he said.

"We set out to get a bonus point win. We also set out to concede less than 12 points, and we missed that by a bit. There are pros and cons. It was not all bad. We did a job, but we need to set a standard for what’s coming up in the next two weeks. That will be hugely different from this weekend.

"Yes, we rested a few boys and there were some injuries, but we still have the same standards no matter who takes the field. We weren’t on form, but we got away with it."

It had been a strange game all through. When Glasgow got their attacking play right, they looked world beaters. Nick Grigg, in the centre, seemed to be able to find space at will and was the only realistic candidate for man of the match despite Lamont's brace of scores.

After all, Grigg did play a hand in the first three tries. He started the move that ended with Lee Jones being stopped a yard short for Lamont to pick up and finish the job. He broke from his own 22 on a 70-metre run to the line – though he was caught, the ball was whisked across the field for Fraser Brown, the hooker, to score. Then he broke on his own in midfield and just managed to find Lamont with his pass for the wing to score.

It was mesmerising stuff and might have given Townsend something more to think about as he finalises his plans for Europe.

Even the downside has a silver lining. As soon as Leonardo Sarto, the Italian wing who left Zebre in the summer, had raised something between a groan and a half-hearted cheer by scoring Glasgow's fourth try at his old ground to secure the scoring bonus point, Townsend brought on his replacements.

It was too soon. Zebre still had plenty of fight in them and Giovanbattista Venditti, the wing, got their comeback under way by winning the race to score his side's second try and then they launched a furious and sustained assault on the Glasgow Warriors line.

The glint of hope was the way the youngsters held out. It was backs-to-the-wall stuff and they made every hit count. They held scrums on their line and any number of line-out drives until so late in the game that there was little chance of Zebre being able to repeat the move that put Andries Van Schalwyk, the No8, over.

A late exchange of penalties and Glasgow were home but Zebre had the consolation of a losing bonus point. "The boys just took the foot off a little bit once we got comfortably ahead and had the bonus point," said Lamont.

"If Leicester look at the video they’ll realise that if we repeat the mistakes we will get punished. We can’t afford to do that. It’s about time we got a good run in Europe, and it starts next weekend."

Scorers: Zebre: Try: Fabiani (27), Venditti (54), van Schalwyk (75). Cos: Canna 2. Pens: Canna 3

Glasgow Warriors: Tries: Lamont 2, Brown, Sarto. Cons: Clegg 2. Pens: Clegg 3

Zebre: E Padovani; L Greeff (K Van Zyl, 52), G Bisegni (sin bin: 43-53), T Castello (T Boni, 52), G Venditti; C Canna, G Palazzani (M Violi, 56); A Lovotti (B Postiglioni, 64), O Fabiani (C Festuccia, 70), P Ceccarelli (D Chistolini, 62), J Furno (Q Geldenhuys, 47), G Biagi (C) (F Ruzza, 62), M Mbanda, J Meyer (sin bin: 34-44), A Van Schalkwyk.

Glasgow Warriors: P Murchie; S Lamont, N Grigg (S Hogg, 64), S Johnson, L Jones (L Sarto, 19); R Clegg, A Price (G Hart, 60), G Reid (D Sears-Duru, 52), F Brown (J Malcolm, 53), S Puafisi (Z Fagerson, 33-41, 53), R Harley, R McAlpine (C Hunter-Hill, 54), J Strauss, M Fagerson (sin bin: 34-44, L Wynne, 67), R Wilson (C).

Referee: L Linton (Scotland)

Attendance: 2,000