Did Fernando Alonso and Aston Martin throw away a Monaco win?

MONACO -- With the benefit of hindsight, Fernando Alonso had a clear shot at his 33rd Formula One victory at Sunday's Monaco Grand Prix. Had Aston Martin fitted intermediate wet-weather tyres to his car on Lap 54 instead of slick medium-compound tyres, and had he then completed a clean outlap with Max Verstappen pitting on Lap 55 (as he did in reality), Alonso would have emerged in the lead with 23 laps to run.

Arguably, given the changing track conditions, it's impossible to say what would have happened from Lap 54 onwards. But when you add up how much time Verstappen lost by staying out until the end of Lap 55 on slick tyres, and how much Alonso had to gain by switching to intermediates on Lap 54, it's also a fair assumption that the Aston Martin driver would have taken the lead.

In reality, Aston Martin realised its tyre choice mistake a lap later, called Alonso back into the pits on Lap 55 and he emerged still in second place but 22 seconds behind Verstappen -- a gap that only grew over the remaining laps.

What do the lap times tell us?

When Alonso pitted on Lap 54, his gap to Verstappen in the lead was under nine seconds. Alonso's in-lap on Lap 54 was 20 seconds faster than Verstappen's in-lap on Lap 55, suggesting he would have made up more than the nine seconds he needed had Aston Martin fitted intermediate tyres on Lap 54 and not needed to make a second pit stop on Lap 55.

Esteban Ocon, who finished third, offers a useful comparison as he did switch to intermediates on Lap 54, and took 15 seconds out of the Red Bull's lead as a result. It's true that Ocon was 30 seconds further behind Alonso in the race when he stopped on Lap 54, meaning Alpine had more time to assess the changing track conditions as they got worse, but it still suggests Alonso would have easily found the nine seconds he needed by switching to intermediates on Lap 54.

Further proof of the advantage Alonso could have gained was offered by his teammate. Lance Stroll switched to intermediates at the end of Lap 51 and on Lap 53, his first full flying lap on the wet crossover tyre, he set a 1:32.189 pace. Although Alonso and Verstappen were both faster using slick tyres on Lap 53, Verstappen's pace then slipped to 1:38.964 on Lap 54 -- showing how much of an advantage could have been gained by using intermediates versus slicks from Lap 54 onwards.

Why didn't Aston Martin fit intermediates on Lap 54?

After the race, Alonso seemed surprised so many journalists were questioning the team's strategy. Second place at Monaco is a very strong result for the team, and he delivered it with an impressive drive. What's more, the result means he is now just 12 points off Red Bull's Sergio Perez in the fight for second place in the championship.

Unlike Verstappen, Alonso started Sunday's race on hard tyres in the hope that the durability of the compound would give him more strategy options later in the race. Although he sacrificed a small amount of performance in the opening part of the grand prix, the strategy worked perfectly as he stood to benefit had the team made the most of the wet weather and switched to intermediates on Lap 54.

In Aston Martin's defence, the rainstorm that hit the track was initially isolated to Portier and it wasn't clear if it would ease off rather than intensify.

"Very wet through [Turns] 7 and 8, probably good for inters," Alonso said on team radio. "But rest of the track would probably be too dry -- I don't know, mate."

After the race, Alonso added: "For me, it was very clear that the track on that lap we stopped was completely dry, apart from Turn 7 and 8, so how could I put on the inters? It was completely dry -- 99% of the track.

"So I stopped for drys. The weather forecast, it was a small shower, a small quantity of rain as well what we had as a team.

"And we had a lot of margin behind us to put the dry tyres and if necessary the inter tyres. Maybe it was extra safe, I don't know.

"That minute and a half that it took to go through Turn 5, 6, 7 and 8 again, it changed completely. The outlap on the dry tyres, it was very wet when I got to those corners. The lap that we stopped, it was completely dry."

Speaking shortly after the race, Aston Martin team principal Mike Krack said he wasn't sure if the decision had cost the team the race, but justified the thought process on the pit wall.

"The fact is obviously you try to stay out as long as you can in such conditions when you do not really know what's going to happen," he said. "We did not anticipate so much rain, to be honest, so we thought that it would just be a short shower and dry quickly because the track was very hot.

"Then normally we say, 'OK, we stay out one or two or three more laps,' but the tyres were worn already quite a lot and we saw the temperatures going down, so that was a bit of a risk.

"When the car came in with this information, we said, 'OK, let's fit the mediums,' but then when the car left, I mean shortly after, we saw there was really a lot of rain and we had to come back."

One factor Aston Martin could not have foreseen was Verstappen making a big mistake on his in-lap at Portier. On slick tyres, Verstappen ran wide, slid along the barrier and then continued, costing him significant time. Had he not made the mistake, arguably he still would have had a big enough buffer over Alonso to pit a lap later for intermediates and still retain the lead.

"When a world-class driver like Max goes out like that, you know, you think it's better you don't do this as well," Krack said. "So at the end of the day these are calls that are made within a very short amount of time when you have not maybe the same information as everybody.

"It depends on where your driver is on the track and where he is in the garage. So I think overall we must not be too greedy. We should look back and see what were our objectives."

Did Aston Martin mess up?

Hindsight is a wonderful thing, and applied to Alonso's race it's clear a victory in Monaco was possible. But at the time the decision was made, and with a forecast that had predicted no rain at all earlier in the race, it's easy to understand why Aston Martin got the call wrong.

An unwritten rule of F1 strategy is that you fit the tyres to suit the track conditions, and at the time of Alonso's in-lap the majority of the track was still suited to slicks. The section that was wet was on the far side of the Principality and the pit lane, where the decision was ultimately made, was still completely dry.

Had the conditions improved from lap 54 onwards, the soft rubber of the intermediate tyre would have been torn apart by the dry track surface around the track and Alonso would have been forced to pit again but for mediums.

Perhaps the biggest shame of all is the battle that didn't happen. If Verstappen emerged behind Alonso after his pit stop, it would have set up a fascinating battle between two great drivers with the faster of the two cars in second place. Monaco is incredibly difficult to overtake at, but with Verstappen chasing for victory all bets would have been off for 23 laps of thrilling racing.