Команда знатоков опередила нас в командном зачёте.

Because the subject is команда, and команда is a feminine singular noun in Russian.

In the past tense, Russian verbs agree with the subject in gender and number:

• опередил = masculine singular
• опередила = feminine singular
• опередило = neuter singular
• опередили = plural

So:

• Команда опередила... = The team overtook / outpaced...

Even though a team contains many people, the noun команда itself is grammatically singular and feminine.

Because знатоков is the genitive plural of знаток.

Here, it depends on команда:

• команда знатоков = a team of experts / a team of connoisseurs / a team of knowledgeable people

This is a very common Russian pattern:

• группа студентов = a group of students
• команда игроков = a team of players
• отряд солдат = a squad of soldiers

So знатоков is used because Russian often says “team of X” with X in the genitive plural.

The singular знаток means someone who knows a subject very well: an expert, connoisseur, or knowledgeable person.

Depending on context, команда знатоков could mean:

• a team of experts
• a team of connoisseurs
• a team of quiz experts / knowledgeable players

In some contexts, especially games or intellectual competitions, знатоки can refer to people known for their knowledge rather than formal specialists.

Because опередить takes a direct object, and the direct object goes in the accusative case.

The pronoun мы changes like this:

• мы = we
• нас = us

So:

• опередила нас = overtook us / got ahead of us

This is just the normal object form of the pronoun.

Опередить means something like:

• to overtake
• to get ahead of
• to outpace
• to beat someone to something

In this sentence, it means the team finished ahead of us in some ranking or results table.

It is often used in both literal and figurative senses:

• literally: one runner overtakes another
• figuratively: one team ranks above another

Yes. Опередить is perfective.

That means it presents the action as a completed result:

• they did get ahead of us
• they ended up ahead of us

The imperfective partner is usually опережать, which describes the process, repetition, or general fact:

• Они нас опережают. = They are ahead of us / They keep outpacing us.
• Они нас опередили. = They got ahead of us / They overtook us.

So in your sentence, the perfective form suggests a completed outcome in the standings.

It means something like:

• in the team standings
• in the team ranking
• in the team classification
• in the team event / team results

The noun зачёт can mean a counted result, ranking, or officially recorded score/result, depending on context.

So командный зачёт is the category where results are counted by team, not individually.

For example, a competition may have:

• личный зачёт = individual standings
• командный зачёт = team standings

It is the prepositional case after в, because here в means in in the sense of within a category / in the standings.

Base form:

• командный зачёт

Prepositional singular:

• в командном зачёте

You can see both words change:

• командный → командном
• зачёт → зачёте

So the phrase literally means in the team classification/standing.

They are related, but they are different parts of speech:

• команда = team (noun)
• командный = team / team-based (adjective)

So:

• команда знатоков = the team of experts
• в командном зачёте = in the team standings

This is similar to English using both team and team-based/team in different roles.

Yes. Russian word order is flexible, because the cases show the grammatical roles.

The neutral order here is:

• Команда знатоков опередила нас в командном зачёте.

But other orders are possible for emphasis, for example:

• В командном зачёте команда знатоков опередила нас.
  • emphasis on in the team standings
• Нас команда знатоков опередила в командном зачёте.
  • emphasis on us

The original sentence sounds natural and neutral.

Yes, the dictionary form is зачёт, with ё.

In Russian writing, ё is often replaced by е, so you may also see:

• зачете

But it is still pronounced zach-YO-te in this form, not za-che-te.

For learners, it is helpful to remember the real spelling:

• зачёт
• в зачёте

because ё tells you where the stress and pronunciation go.

Russian does not have articles like a or the.

So Команда знатоков can mean:

• the team of experts
• a team of experts

The exact meaning depends on context.

In this sentence, English will often use the because the team is probably already known from the context, but Russian simply does not need an article.