Dave rennie praised his team's effort but said decision making needs to be better

Warriors had the better of the early exchanges but found themselves behind when a Saracens line-out on halfway gave them a platform to make ground with Mike Rhodes eventually touching down for the try. Inexplicably, referee Mathieu Raynal and his officials didn't see a Saracens player clearly in touch in the build up to the score. Owen Farrell kicked the conversion.

Warriors were further punished minutes later for straying offside and that allowed Farrell to step up and put the ball through the posts.

Saracens were then the team caught offside, giving Adam Hastings the chance to reduce the Glasgow deficit and he made no mistake from in front of the sticks.

The Scottish side were penned in their own 22 when they won a scrum before the interval but the call was surprisingly overturned after a push by Fraser Brown. That gave Farrell the simple task of slotting between the posts to make it 13-3 at half time.

Warriors had several chances in the second half to put points on the board but opted for the corner on each occasion as they failed to puncture the Saracens line, meaning the second half finished scoreless.

Warriors play Cardiff Blues next, with the Welsh side having triumphed 30-21 away to Lyon earlier on Sunday.

"I really rate all the effort," said Glasgow Head Coach Dave Rennie after the match.

"We gave away soft points early and we got into a bit of an arm wrestle. We just need to show a lot more composure with the ball in hand.

"We're trying to pull out the miracle play. That's the disappointing factor, just turnover ball at critical times.

"A couple of times we could have kicked smarter to relieve pressure. Maybe some of our decision making wasn't good enough in the end but you can't fault attitude.

"It was a big step up but we need to be clinical when you get opportunities and be patient and so on. We're going to have to turn that around quickly next week."

The home crowd grew increasingly frustrated by some of referee Mathieu Raynal's calls.

"I think Maro Itoje is a law unto himself, seems to get away with a fair bit," said Rennie of the Saracens flanker.

"Maybe they're a bit more streetwise in instigating some of their stuff and we got punished for it.

"In the end we've got to look at us and what we can do better for next week. We had our chances and we had to do our part better."